P0134 O2 Sensor Sensor Circuit No Activity

[7rrivera7]

2000 Jetta VR6:

Idled fine before replacing the pre-cat O2 sensor with a new Bosch unit since the original O2's wiring was frayed. Now the idle during a cold start is horrible and the engine misses until it warms up. The CTS is a new "green" unit so that gets eliminated from being a possible culprit.

With the new O2 plugged in, a scan gives me the following:

16518 - Oxygen (Lambda) Sensor B1 S1
P0134 - 35-00 - No Activity

If I unplug the O2 sensor, the car idles great both cold and warm and a scan gives me the following:

16518 - Oxygen (Lambda) Sensor B1 S1
P0134 - 35-00 - No Activity
17524 - Oxygen (Lambda) Sensor Heating; B1 S1
P1116 - 35-00 - Open Circuit

This tells me the PCM detected that I unplugged the O2 sensor so I guess most of the wiring is good but I'm thinking one (or more?) wire(s) is open/shorted since I get "no activity" with the O2 plugged in.

I'm ready to trace the O2 wiring but I having difficulty in reading the diagram in the Bentley. The O2 sensor has 5 wires as follows:

red, white, yellow, black, grey

The O2 wiring harness has 6 wires as follows:

green, blue/yellow stripe, orange, orange(2), white, black

When connected, the color to color matching is as follows:

O2 black to connector green
O2 grey to connector blue/yellow stripe
O2 yellow to connector orange
O2 red to connector orange(2)
O2 white to connector white
O2 (open) to connector black

As shown, the O2 sensor has 5 wires and the harness connector has 6 - the black wire on the O2 connector has nothing coming from the sensor. Is it possible I bought the wrong sensor and the black wire is the signal which shows "no activity"? The original O2 sensor with frayed wiring was also a 5-wire unit.

Sorry for the lenghty post but I think more details is better than less right?

Thanks!

[vdubtech398]

Not sure about the rough idle caused by new O2 sensor, but VW issued a software update/ECM software update for the P0134 concern on VR6's like the one you have, I would call a local dealer and ask them to run your VIN and check for an N7/26E1 campaign/ reflash.

Maybe try cleaning your throttle body to clear up your cold start rough idle.

[Jack@European Parts]

Respectfully you need to post an auto-scan to commence here.

We would know for sure if he needed an N7 update if there was this thing called an....


AUTO-SCAN!

[7rrivera7]

No problem - thought the info posted was sufficient for the cause at hand. Here is an autoscan:

VCDS Version: Release 11.11.3 (x64)
Data version: 20120401

Wednesday,16,May,2012,08:30:52:26610

Chassis Type: 9M - VW Jetta IV
Scan: 01 02 03 08 09 15 16 17 19 22 29 35 36 37 39 46 47 55 56 57
75 76

Mileage: 130380km/81014miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 021-906-018-AFP.lbl
Part No: 021 906 018 K
Component: MOTRONIC ME7.1 G V06
Coding: 00033
Shop #: WSC 00862
VCID: 162D3A84729CBC9

2 Faults Found:
16518 - Oxygen (Lambda) Sensor B1 S1
P0134 - 35-00 - No Activity
17524 - Oxygen (Lambda) Sensor Heating; B1 S1
P1116 - 35-00 - Open Circuit
Readiness: 0000 1101

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01M-927-733.lbl
Part No: 01M 927 733 JS
Component: AG4 Getriebe 01M 4834
Coding: 00000
Shop #: WSC 00000
VCID: 8A15DEF4B624E89

1 Fault Found:
00777 - Accelerator Position Sensor (G79)
27-10 - Implausible Signal - Intermittent

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 1J0-907-37x-ABS.lbl
Part No: 1J0 907 379 R
Component: ASR 20 IE CAN 0001
Coding: 13204
Shop #: WSC 00066
VCID: 4081BCDC4098E29

1 Fault Found:
01276 - ABS Hydraulic Pump (V64)
16-00 - Signal Outside Specifications

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 3Bx-907-044.lbl
Part No: 3B1 907 044 A
Component: CLIMATRONIC S 9.0
Coding: 01000
Shop #: WSC 00066
VCID: 1F431FA09DA6FD1

3 Faults Found:
00792 - A/C Pressure Switch (F129)
35-00 - -
01206 - Signal for Duration of Ignition Off Time
35-00 - -
00281 - Vehicle Speed Sensor (G68)
35-10 - - - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl
Part No: 6Q0 909 605 A
Component: 09 AIRBAG VW5 0003
Coding: 12345
Shop #: WSC 00066
VCID: 356FDD080F5A571

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 1J0-920-xx0-17.lbl
Part No: 1J0 920 920 D
Component: A4-KOMBIINSTR. VDO V54
Coding: 07262
Shop #: WSC 08701
VCID: 254F0D48BFFA271

Subsystem 1 - Part No: IMMO
Component: IDENTNR: VWZ7Z0X1298917
IMMO-IDENTNR: VWZ7Z0X1298917

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels: 6N0-909-901-19.lbl
Part No: 6N0 909 901
Component: Gateway K<->CAN 0001
Coding: 00007
Shop #: WSC 00066
VCID: F0E1AC1CB0B8B29

No fault code found.

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr Labels: None
Part No: 3B1 9€9 760 A
Component: Sitzverstellung FS 0003
VCID: 76ED1A0452DC1C9

4 Faults Found:
00668 - Supply Voltage Terminal 30
06-10 - Signal too High - Intermittent
00668 - Supply Voltage Terminal 30
07-10 - Signal too Low - Intermittent
01330 - Central Control Module for Central Convenience (J393)
49-10 - No Communications - Intermittent
01009 - Sensor for Driver's Seat Position Fore/Aft (G218)
36-00 - Open Circuit

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 1J0-959-799.lbl
Part No: 1J0 959 799 AJ
Component: 61 Zentral-SG Komf. 0001
Coding: 04098
Shop #: WSC 00066
VCID: 860DEAC4A23C8C9

Subsystem 1 - Part No: 1J1959801C
Component: 61 Tõrsteuerger. FS0002r

Subsystem 2 - Part No: 1J1959802D
Component: 61 Tõrsteuerger. BF0002r

Subsystem 3 - Part No: 1J4959811C
Component: 61 Tõrsteuerger. HL0002r

Subsystem 4 - Part No: 1J4959812C
Component: 61 Tõrsteuerger. HR0002r

6 Faults Found:
01330 - Central Control Module for Central Convenience (J393)
53-10 - Supply Voltage Too Low - Intermittent
01179 - Incorrect Key Programming
35-00 - -
01331 - Door Control Module; Driver Side (J386)
53-10 - Supply Voltage Too Low - Intermittent
01332 - Door Control Module; Passenger Side (J387)
53-10 - Supply Voltage Too Low - Intermittent
01333 - Door Control Module; Rear Left (J388)
53-10 - Supply Voltage Too Low - Intermittent
01334 - Door Control Module; Rear Right (J389)
53-10 - Supply Voltage Too Low - Intermittent

End ---------------------------------------------------------------------

[Jack@European Parts]

Thank you for posting the auto-scan.

You need the firmware update.

You need a MAF and new OXS sesnors.
Add fuses for the OXS sensors, or you will burn an ecu down.

Verify false air leaks and exhaust leaks corrected.
I see LDP, EVAP, SAI, and cat tests not completed.

[7rrivera7]

Thank you Jack.

The MAF is new and so are both O2 sensors. Readiness is not complete because the car is in my garage on stands while I resolve various suspension issues. It hasn't been driven for more than 5 minutes in the last few months and the battery has been disconnected.

Can you validate that even though the primary O2 sensor has only 5 wires and the O2 harness connector has 6, this is normal? I'd like to tackle one problem at a time and since the O2 sensor has "no activity" when plugged in, I need to know if the wiring is correct since the orioginal O2 wiring was frayed.

The key message I want to present is that with the O2 plugged in, my cols start idle is horrible and when it is unplugged, the idle is smooth. This leads me to believe the "no activity" response from the PCM is causing the bad idle.

[7rrivera7]

When you say I need the firmware update, is this at the dealer under a TSB? Do you have info on this? Thanks again!

[Dana @ Ross-Tech]

When you say I need the firmware update, is this at the dealer under a TSB? Do you have info on this? Thanks again!

N7 (26E1) was a recall issues in 2006 or 2007 for all AFP Vr6 vehicles in the US market and should be completed free of charge on any vehicles with a clean title providing the action is open on this VIN. That particular module (021 906 018 K) would be updated from the SWL of V06 to 6758 or higher.

[Jack@European Parts]

Validated it has an extra pin for the 6th.

[7rrivera7]

Validated it has an extra pin for the 6th.

Thank you so much for validating this for me Jack!

...so the O2 sensor has 5 wires in a 6-pin connector and even though the 6th pin is not connected to anything, this is by design and not the cause of my "no activity" O2 code.

It's time to trace the 5 wires into the PCM. Anyone know what pins these 5 wires go to on the PCM? I have the Bentley and if someone can help me understand the wiring diagrams, I can help myself

[Jack@European Parts]

CORRECT

You must find a different path of attack.

Use VCDS to watch OXS in 01-04-034 for B1 S1.

[7rrivera7]

CORRECT

You must find a different path of attack.

Use VCDS to watch OXS in 01-04-034 for B1 S1.

Will attempt this and report back...

[Jack@European Parts]

Then also report deviation logged of 031 and 032

[7rrivera7]

Ok, I've got the logs requested but I'm not allowed to post attachments. How can I get the 3 .CSV files to you?

[7rrivera7]

Jack I sent the logs to: vwemporium@aol.com. Hope this is what you intended

[Jack@European Parts]

Nope please post them here for everyone to see.

[7rrivera7]

Ok, I tried formatting as best I could before copying. Saw the "TEST OFF" column but don't understand VCDS enough to turn it on...

OXS in 01-04-034 for B1 S1

Friday 18 May 2012 21:05:49:26610 VCDS Version: Release 11.11.3 (x64) Data version: 20120401
021 906 018 K MOTRONIC ME7.1 G V06

Group A: '034 Group B: Not Running Group C: Not Running
Engine Speed Catalytic Converter Dynamic Factor Result
TIME (G28) Bank 1 Temp. Bank 1 Sensor 1 Lambda Aging TIME TIME
Marker STAMP /min °C STAMP STAMP
0.01 920 340 0.797 Test OFF
0.3 880 340 0.797 Test OFF
0.6 800 335 0.797 Test OFF
0.9 840 335 0.797 Test OFF
1.2 800 335 0.797 Test OFF
1.5 840 335 0.797 Test OFF
1.8 800 335 0.797 Test OFF
2.1 880 330 0.797 Test OFF
2.4 840 330 0.797 Test OFF
2.7 720 330 0.797 Test OFF
3 760 330 0.797 Test OFF
3.3 760 330 0.797 Test OFF
3.6 760 330 0.797 Test OFF
3.9 800 330 0.797 Test OFF
4.2 800 325 0.797 Test OFF
4.5 800 325 0.797 Test OFF
4.8 840 325 0.797 Test OFF
5.1 800 325 0.797 Test OFF
5.4 760 325 0.797 Test OFF
5.7 760 325 0.797 Test OFF
6 720 320 0.797 Test OFF
6.3 760 320 0.797 Test OFF
6.6 760 320 0.797 Test OFF
6.9 720 320 0.797 Test OFF
7.2 760 320 0.797 Test OFF
7.49 760 320 0.797 Test OFF
7.8 760 315 0.797 Test OFF
8.1 800 315 0.797 Test OFF
8.4 800 315 0.797 Test OFF
8.7 720 315 0.797 Test OFF
9 720 315 0.797 Test OFF
9.3 720 315 0.797 Test OFF
9.6 680 315 0.797 Test OFF
9.9 640 315 0.797 Test OFF
10.2 680 310 0.797 Test OFF
10.5 760 310 0.797 Test OFF
10.8 720 310 0.797 Test OFF
11.1 760 310 0.797 Test OFF

OXS in 01-04-031 for B1 S1

Friday 18 May 2012 21:14:59:26610 VCDS Version: Release 11.11.3 (x64)
021 906 018 K MOTRONIC ME7.1 G V06

Group A: '031
Lambda Control Lambda Control Bin. Bits Bin. Bits
TIME Bank 1 (actual) Bank 1 (specified)
Marker STAMP
0.28 0.75 1
0.59 0.75 1
0.88 0.75 1
1.19 0.75 1
1.49 0.75 1
1.79 0.75 1
2.08 0.75 1
2.39 0.75 1
2.69 0.75 1
2.99 0.75 1
3.29 0.75 1
3.59 0.75 1
3.89 0.75 1
4.18 0.75 1
4.49 0.75 1
4.78 0.75 1
5.09 0.75 1
5.39 0.75 1
5.69 0.75 1
5.98 0.75 1
6.29 0.75 1
6.58 0.75 1
6.89 0.75 1
7.19 0.75 1
7.49 0.75 1
7.78 0.75 1
8.09 0.75 1
8.39 0.75 1
8.7 0.75 1
8.99 0.75 1
9.28 0.75 1
9.59 0.75 1
9.89 0.75 1
10.19 0.75 1
10.49 0.75 1
10.78 0.75 1
11.08 0.75 1

OXS in 01-04-032 for B1 S1

Friday 18 May 2012 21:16:10:26610 VCDS Version: Release 11.11.3 (x64)
021 906 018 K MOTRONIC ME7.1 G V06

Group A: '032
Adaptation (Idle) Adaptation (Partial) Bin. Bits Bin. Bits
TIME Bank 1 Sensor 1 Bank 1 Sensor 1
Marker STAMP % %
0.01 -3.4 0
0.3 -3.4 0
0.6 -3.4 0
0.9 -3.4 0
1.2 -3.4 0
1.49 -3.4 0
1.8 -3.4 0
2.1 -3.4 0
2.39 -3.4 0
2.7 -3.4 0
2.99 -3.4 0
3.3 -3.4 0
3.59 -3.4 0
3.9 -3.4 0
4.2 -3.4 0
4.5 -3.4 0
4.8 -3.4 0
5.09 -3.4 0
5.4 -3.4 0
5.7 -3.4 0
5.99 -3.4 0
6.29 -3.4 0
6.6 -3.4 0
6.9 -3.4 0
7.2 -3.4 0
7.5 -3.4 0
7.79 -3.4 0
8.09 -3.4 0
8.4 -3.4 0
8.7 -3.4 0
9 -3.4 0
9.29 -3.4 0
9.6 -3.4 0
9.9 -3.4 0
10.2 -3.4 0
10.49 -3.4 0
10.8 -3.4 0
11.09 -3.4 0

[7rrivera7]

Ok, I just saw and email from Jack stating I did not run the test properly - sorry. I will repost...

[7rrivera7]

Reposting OXS in 01-04-034 for B1 S1 as I did not activate the test previously. 031 and 034 remained the same so I won't repost those.

021 906 018 K MOTRONIC ME7.1 G V06

Group A: '034 Group B:
Engine Speed Catalytic Converter Dynamic Factor Result
TIME (G28) Bank 1 Temp. Bank 1 Sensor 1 Lambda Aging TIME
Marker STAMP /min °C STAMP
0.01 760 165 0.797 B1-S1 Not OK
0.3 760 165 0.797 B1-S1 Not OK
0.59 760 170 0.797 B1-S1 Not OK
0.89 760 170 0.797 B1-S1 Not OK
1.18 800 170 0.797 B1-S1 Not OK
1.48 800 170 0.797 B1-S1 Not OK
1.79 800 170 0.797 B1-S1 Not OK
2.09 760 170 0.797 B1-S1 Not OK
2.39 760 170 0.797 B1-S1 Not OK
2.69 840 170 0.797 B1-S1 Not OK
2.99 1000 175 0.797 B1-S1 Not OK
3.29 1160 175 0.797 B1-S1 Not OK
3.59 1200 180 0.797 B1-S1 Not OK
3.89 1280 180 0.797 B1-S1 Not OK
4.19 1320 180 0.797 B1-S1 Not OK
4.49 1360 180 0.797 B1-S1 Not OK
4.78 1280 180 0.797 B1-S1 Not OK
5.09 1200 180 0.797 B1-S1 Not OK
5.39 1120 180 0.797 B1-S1 Not OK
5.68 1040 180 0.797 B1-S1 Not OK
5.99 960 180 0.797 B1-S1 Not OK
6.29 920 180 0.797 B1-S1 Not OK
6.59 880 180 0.797 B1-S1 Not OK
6.89 800 180 0.797 B1-S1 Not OK
7.18 800 180 0.797 B1-S1 Not OK
7.49 800 180 0.797 B1-S1 Not OK
7.79 840 180 0.797 B1-S1 Not OK
8.09 960 180 0.797 B1-S1 Not OK
8.39 1160 185 0.797 B1-S1 Not OK
8.69 1280 185 0.797 B1-S1 Not OK
8.99 1360 190 0.797 B1-S1 Not OK
9.29 1400 190 0.797 B1-S1 Not OK
9.59 1360 190 0.797 B1-S1 Not OK
9.89 1320 190 0.797 B1-S1 Not OK
10.19 1320 190 0.797 B1-S1 Not OK
10.49 1160 190 0.797 B1-S1 Not OK
10.79 1080 190 0.797 B1-S1 Not OK
11.09 960 190 0.797 B1-S1 Not OK
11.38 840 185 0.797 B1-S1 Not OK
11.69 800 185 0.797 B1-S1 Not OK
11.99 760 185 0.797 B1-S1 Not OK
12.29 720 185 0.797 B1-S1 Not OK
12.58 760 185 0.797 B1-S1 Not OK
12.89 800 185 0.797 B1-S1 Not OK
13.18 840 190 0.797 B1-S1 Not OK
13.49 1000 190 0.797 B1-S1 Not OK
13.79 1320 195 0.797 B1-S1 Not OK
14.09 1640 200 0.797 B1-S1 Not OK
14.39 1800 205 0.797 B1-S1 Not OK
14.69 1480 200 0.797 B1-S1 Not OK
14.99 1320 200 0.797 B1-S1 Not OK
15.29 1200 200 0.797 B1-S1 Not OK
15.57 1040 200 0.797 B1-S1 Not OK
15.89 960 200 0.797 B1-S1 Not OK
16.19 840 195 0.797 B1-S1 Not OK
16.49 800 195 0.797 B1-S1 Not OK
16.79 880 195 0.797 B1-S1 Not OK
17.08 1040 200 0.797 B1-S1 Not OK
17.38 1280 205 0.797 B1-S1 Not OK
17.68 1480 205 0.797 B1-S1 Not OK
17.98 1720 215 0.797 B1-S1 Not OK
18.28 1920 215 0.797 B1-S1 Not OK
18.58 2000 220 0.797 B1-S1 Not OK
18.89 1880 220 0.797 B1-S1 Not OK
19.18 1600 215 0.797 B1-S1 Not OK
19.48 1360 215 0.797 B1-S1 Not OK
19.78 1160 210 0.797 B1-S1 Not OK
20.08 1040 210 0.797 B1-S1 Not OK
20.37 960 210 0.797 B1-S1 Not OK
20.68 880 210 0.797 B1-S1 Not OK
20.98 840 210 0.797 B1-S1 Not OK
21.27 760 205 0.797 B1-S1 Not OK
21.58 720 205 0.797 B1-S1 Not OK
21.87 760 205 0.797 B1-S1 Not OK
22.18 760 205 0.797 B1-S1 Not OK
22.47 760 205 0.797 B1-S1 Not OK
22.77 720 205 0.797 B1-S1 Not OK
23.08 760 200 0.797 B1-S1 Not OK
23.37 760 200 0.797 B1-S1 Not OK
23.68 720 200 0.797 B1-S1 Not OK
23.97 720 200 0.797 B1-S1 Not OK
24.28 720 200 0.797 B1-S1 Not OK
24.57 720 200 0.797 B1-S1 Not OK
24.88 760 200 0.797 B1-S1 Not OK
25.17 760 200 0.797 B1-S1 Not OK

[7rrivera7]

Ok, so while I wait for a response, I decided to trace the wiring from the O2 harness connector to the ECM. After studying the Bosch LSU and Bentley wiring diagrams, I figured out the BLACK wire on the LSU (VS) is the signal to the ECM. This wire goes to the GREEN wire on the O2 harness which leads to PIN 70 on the ECM. I pulled out my multi-meter and validated continuity to PIN 70 on the ECM.

My troubleshooting leads me to beleive the O2 circuitry on the ECM has been compromised, most likely due to the original O2 sensor wiring which was frayed.

Before looking for a replacement ECM, I am going to remove it and trace O2 input pin 70 into the main board to see if I find any burnt, open or out of range components.

I will report back...

[7rrivera7]

Ok, while attempting to open the ECM, I noticed it is weather sealed so I've decided to leave it along and not break said seal. I found one on Ebay for $99 so I'm covered.

Before buying the ECM, I'm going to make sure my O2 sensor is actually SENDING a signal to it even though it is new - you never know.

...I'll report back

[7rrivera7]

I back probed the O2 sensor for voltage on the GREEN wire which is the input tp the ECM on pin 70 and it stays at a constant 2.4v.

The testing procedure I have says after the car is in closed loop, the voltage should fluctuate above and below .45 volts but it's not happening. The car has been idling for over 20 minutes and for 1 of those minutes , I held the revs at 3000 trying to force closed loop.

The car is at temperature (190) but I don't see anything from the sensor. Could the new sensor be bad? Am I tested correctly?

Please help!

Here is the O2 sensor wiring diagram I am using:

http://wbo2.com/cable/lsuconns.htm

[stan067]

O2 Pin 1 Green to pin 70 ECU
O2 Pin 2 Black to pin 71 ECU
O2 Pin 3 Blue/Yellow to fuse 43 10 amp side of dash. Has power when fuel pump runs.
O2 Pin 4 White to ECU pin 5
O2 Pin 5 Orange/ Purple to ECU pin 51
O2 Pin 6 Orange/Brown to ECU pin 52

I like ohm check the wires and load test with both O2 & ECU disconnected.

Follow these on your Bentley to learn how to read a track wiring diagram. Believe me I know how different V.W. track wiring diagram can be. Takes a lot of practice.

Good Luck

[7rrivera7]

I like ohm check the wires and load test with both O2 & ECU disconnected.

Wow Stan thanks for that info - it'll definately help me learn the wiring diagrams and help me test the rest of the O2 wiring for continuity into the ECM

What can you tell me about the O2 sensor? Am I testing correctly by monitoring the GREEN wiring for a crossover voltage?

I just realized the Innovative wideband on my drag Civic uses the same O2 sensor so I'll be swapping it in today to see if works any different from the one currently installed on the Jetta.

I quoted you on the ohm check and load testing. Ohm checking is continuity right? What exactly is load testing and how do I do that?

Thanks again buddy!

[stan067]

Disconnect the ECU & the O2.
With a DVOM meter put one end in pin 1 of O2 connector and the other in pin 70 of the ECU. Set meter to ohm’s and you should have less then .5 ohm’s ½ an ohm. This is the amount of resistance in the wire. Less is better more is bad.

Load test is actually putting power on the wire at one end and go to the other end with a test light to see if the light lights. You are actually running power thru the wire to test it.
The load is the amount your test light takes to light up.
Most test lights don’t have much of a load so this would be a low load test.
If you take an old head light bulb and connect wires to the light and make a test light with a headlight bulb this will draw a few amps (more power).
A test light draws very little power like a flash light bulb so it’s not a good load tester.
The head light bulb draws a lot more power to light more then is needed for O2 & ECU circuit.
So if each wire lights up a head light bulb you know it can carry a load. “Load test”
Don’t leave the head light bulb on for a long time it gets hot and if it draws too much currant for the size of the wire it will get hot and melt. And these are small wires just light them for a few seconds and you are done and know 100% the wire is good and can carry a load of a few amps. Which is more power then the circuit will ever need.

I don’t like the idea of swapping O2 sensors with another type of car! Unless you really know what you are doing and you don’t. LOL

Post the part # of the new O2 sensor and where you got it?

If the O2 is good and the wiring is load tested then I’d start to think ECU is bad.

That’s it for your basic electricity class…

Good Luck

[7rrivera7]

Thank you Stan!

...actually, I know a lot more than you think but that's not important right now

I tested continuity on the 5 sensor wires to the ECM and fuse #43 and they checked out good and since I was anxious to swap the O2 sensor, I decided to perform the ohm and load tests later.

I swapped the sensor with a spare I have from my Innovative Wideband controller which I use to tune my drag Civic. I've got 3 used and 1 new sensor and it is exactly the same one used on the Jetta - Bosch LSU-4.2 #17014 (0 258 007 057), VW part #021-906-262B.

I performed a Free-Air calibration on one of the spare sensors to make sure it was working and plugged it into the Jetta's pre-cat bung...

I got the same code

I decided to run the following tests with VCDS:

1) Block 030: Oxygen Sensor Regulation

I can see the alternating heater on / heater off so this test passed

2) Block 032: Oxygen Sensor Control Learned Values

Value should be somewhere between -10 and +10%. My value is -2.3% so this test also passed

3) Block 033: Pre-Cat Oxygen Sensor Control

Value should fluctuate at least 2% in the -10 to +10% range. My value is 0.0% - FAILED

4) Block 036: Post-Cat Oxygen Sensor Control

Ran the test by depressing the brake pedal, the RPMs rose to 1400, the field 1 voltage fluctuated between .45 and .50v and the test ended with B1-S2 OK. This was expected as I've never gotten a code for the post-cat sensor.

5) Block 034: Aging of the Pre-Cat Oxygen Sensor

This test is similar to the Block 036 test procedure-wise. The "aging value" must be above 0.80 and my value stayed a 0 and the test ended with "B1-S1 NOT OK"

I also decided to test my cat using Block 046. The value should be below 0.50 and my value was 0.35 which means my cat is "efficient". The test never completed though but I think it's due to my failing pre-cat O2 sensor.

My troubleshooting process, which I have outlined here for the benefit of others dealing with this issue, leads me to believe my ECM has a failing O2 sensor control circuitry which was most likely caused by the original O2 sensor with frayed touching wires that was installed when I bought the car.

I still have to ohm and load test the O2 harness and will be doing that next before purchasing a ECM.

[7rrivera7]

Ohm tested the O2 harness wiring and got between .5 and .6 ohms on all the wires - PASSED.

Not sure if load testing is necessary at this point...

[stan067]

You are correct you know more then I thought. Didn’t mean anything by it!

V.W. wiring is weak so I load test! Your time, your money, your car, your call…

Your theory is sound and possible about the ECU.

1.8 T motors loose throttle control from the ECU pedal controls when the O2 wires short to heater circuit. Known problem!

If your wires are good get an ECU next step.

Block 032 field 1 & 2 at idle and part load. Is LTFT at idle and at load given twice.
You only gave the value of 1 field and didn’t say was it idle or part?
What’s field 1
What’s field 2

Clearing codes resets the O2 setting for LTFT so check them after a long run.
But I would clear all codes and watch block 001 for fuel control.
If you have a code ECU will default stuff. Once the code sets I don’t trust the data.

Good Luck

[7rrivera7]

Load test passed - time for a new ECU.

I'll report back when I get it installed...

Thanks to both Jack and Stan for your help with this

[Jack@European Parts]

I can test that ecu if you want just to verify and also apply a core credit if you need one.

Is the MAF OE or China land?

Add fuses for that OXS heater circuit.

[7rrivera7]

I can test that ecu if you want just to verify and also apply a core credit if you need one.

Is the MAF OE or China land?

Add fuses for that OXS heater circuit.

I already purchased an OEM ECM on Ebay for $115 shipped.

The MAF is an OEM replacement also purchased on Ebay for $35 shipped. I got lucky on that one because the seller never mentioned OEM on his auction and I found out via pre-purchase messages. There is a lot of China garbage on Ebay though so buyer beware.

Fuses on the heater circuit would be in-line, possibly tucked under the chassis right near the sensors right?

[Jack@European Parts]

Yup that's a good place.

Hope that MAF works out.

Let me know if you need another, or a hand with the data transfer for your immobilizer.

You should be able to adapt that ECU with VCDS if its IMMO 2 0x17-10-00 save clear and your should be ready.

If it 02> IMMO 3 it will need to be done with a pin Geko session or defeated.

[7rrivera7]

Yup that's a good place.

Hope that MAF works out.

Let me know if you need another, or a hand with the data transfer for your immobilizer.

You should be able to adapt that ECU with VCDS if its IMMO 2 0x17-10-00 save clear and your should be ready.

If it 02> IMMO 3 it will need to be done with a pin Geko session or defeated.

Holy sheit! Immobilizer? I'm a n00b!

My main concern was the part number on the ECM and I totally forgot about the IMMO although I have read about it in the past.

Can you give me more details on the exact procedure for adapting the new ECM. I should have it by tomorrow and want to install it asap.

As far as the MAF, it did eliminate a code I had with the original - signal too high or something to that effect. I even put the old one back and the code came back so I know the replacement is good. I will run the MAF tests though as soon as I get the new ECU installed.

Thanks again Jack!

[bearthebruce]

Much of the detail about Immobilizer is found in the Ross-Tech Wiki Immobilizer section.

[stan067]

Go here to figure out which immobilizer you have.

http://wiki.ross-tech.com/wiki/index.php/Immobilizer

If it immobilizer 1 or 2 you can do it. If it 3 as jack said.

Good Luck