been viewing post for a while what a great site. this is what i have just got a hotmax vag and this is whats going on. the anti slip light on the epc light on and cel light on. no a/c could be fuse panel on top of battery looks a little melted changed 2 years ago. now for the codes abs brake reading says engine control module sporatic 013 chect dtc memory, p1425 evap valve short to ground, p1117 oxygen sensor heating circuit b1 s2 short to ground, p1435 secondary air pump relay J299 short to ground, p1421 secondary air injection valve short to ground, p1472 evap leak detection short to ground, p0102 maf sensor signal to low. I tried running the hvac and says link errors as does cent. elec and cent. locks. Any help would be great also on the readiness test cat failed - heat cat passed - evap system failed - sec air sys failed - heated 02 failed - egr passed. Car runs pretty good. 2002 beetle 1.8t thanks in advance everybody.
Thats a ton of codes; as a typical procedure, I would clear ALL the codes and then take the car for a short drive. See what codes come back; when you scan the car again. Your looking for persistent codes that come back; the codes will be stored in the ecm indefinitely until you clear them... so who knows when or why the codes were triggered.
As you noted; the a/c not working can be directly related to the melted fuse box; check out this link for more details. This could also lead to other electrical issues; that can affect other components and possible codes.
If you want to look up each and every one of the codes stored; you can look them up at the rosstech wiki. Use the search feature in the top right hand corner or look up through the links towards the bottom on the page.
1 17525/P1117 - Oxygen (Lambda) Sensor Heating Circuit: B1 S2: Short to Ground
1.1 Possible Symptoms
1.2 Possible Causes
1.3 Possible Solutions
17525/P1117 - Oxygen (Lambda) Sensor Heating Circuit: B1 S2: Short to Ground
Malfunction Indicator Light (MIL) ON
Failed O2 sensor heater circuit
Wiring Harness issue
Inspect and test O2 sensor heater circuit as per repair manual
Inspect and test wiring harness as per wiring diagram
Replace ECM if O2 sensor and wiring harness are to factory design
I pulled the 02 sensor; tested as per the bentley manual procedure and found mine to be bad. I ordered a new one from my local Autozone (oem bosch) and was good to go, I tried to clear the codes with the VCDS scanner but had to touch the positive and negative battery cables to fully clear the 02 sensor code. Was a easy fix and easy to install on a lift, not too bad. The car seemed to run better and the exhaust; didn't seem to be as rich (black residue was around the tail pipe).
The secondary air injection system; has a few typical problems that come up on the mark iv cars.
On mine; the combi valve failed and I had leaks from the hoses breaking, some of the hoses that come off the valve cover break/split as well. Does the air pump come on; when you start the car? The pumps die, stop turning or seize up (rubber mounts break, making it noisy; on some pumps the rivets break, leak pressure); you could check it with 12V power and see if it spins.
Look up all those codes for more info. I find it hard to believe all of those electrical issues and failures happened at once, you may have a electrical problem that is related to all those components are connected to (wiring connectors, harness resistance, melted wiring/connectors/fuse box etc.). If your battery fuse box is melted; that is a symptom of a greater problem. Known issues related to that: wiring harness to alternator has too much resistance (replace), corroded connections (clean/repair), fan failing (both speeds work? binding or turning freely?), a/c compressor failing causing too much load?... many possibilities but it all requires troubleshooting and step by step process of elimination.
Don't let all the codes overwhelm you; many times they are "clues" to a greater issue that you need to figure out! Clear your codes; take a drive, scan again and let us know what codes come back. Keep us posted as things progress.
there are even more problems, rack and pinion leaking all over maybe in electrical connections no interior lights from doors.. It looks as though I should replace to ground from battery and maybe tranny and definetly the alternator to fuse box above battery as a start.
if i buy a used ecm my concern seems everything points there, do i need to hook it up in dealer parking lot so they can program keys. Can I hook it up to see if et fixes alot of short to ground codes then put the old one back in to drive it to dealer and do above steps. Can I send it out to get fixed and get rid of that stupid immobilizer.