Vehicle: 96 Jetta GLX VR6 Mileage 151K
Place of Birth: Mexico
Engine code AAA 199 582
Failure: Readiness monitors incomplete
Readiness Codes: Complete: Misfire, Fuel and Comp.
Incomplete: Catlyst, Evap,Sec Air, O2 Snsr and O2 Htr.
In troubleshooting the above problem I noticed that the Heated O2 circuit pins 1 (-) & 2 (+) of their connector where not staying a constant battery voltage after the engine was running for 30 seconds. Could someone please tell me where pin 2 of both connectors is connected to. According the manual section 97-295 the upstream 2 shows current track reference 12 and the downstream O2 97-297 current track 42. Maybe it’s me but how do I properly interpret this. If someone could tell me what page these are on or what they go to, I would greatly appreciated it.
I’ve also included a pic indicating that I do not have Heated O2 relay.
Verified that one side of each Heated O2 circuit in connected to the fuel pump relay and the other side of each is connected to the pin 12 and 66 respectively of the ECU. Based on the behavior of the Heated O2 circuit I figured it would be a good idea to check Battery and gnds per the table on 24a-13. And wow, no battery voltage between 10 and 54 and also 33 and 54. I’m assuming that pins 10 and 33 (ECU) are tied together through the Throttle valve motor switch. Verified continuity between ECU pin 10 and the ITA Sensor brown/blue wire. Next step in the morning will be to verify everything so far then identify physically where the gnd connection is for the injector wiring harness…….I hope the hell it’s not under the intake manifold. If somebody has any ideas, feel free.
Does anybody know where the ground termination for the Injector Wiring Harness (Sensor Ground) also called the Motronic Multiport Fuel Injection wiring harness ground (Sensor Ground) is located? I’ve verified the connections based on the manual 97-296 and everything checks out. Is it terminated in the interior via T42/26 or somewhere under the intake manifold (I hope the hell not)? The missing ground explains why there’s no battery voltage between 10 and 54 or 33 and 54 of the ECU connector test on pg. 24a-13 of the manual