EPC light/no start?

Tiny
TELIT1029
  • MEMBER
  • 2012 VOLKSWAGEN PASSAT
  • 2.5L
  • 2WD
  • AUTOMATIC
  • 150,000 MILES
I'm new to message boards and praying someone on here can help me get my car running again. What I've been through since I bought it 2 years ago is exhausting but I'll try and simplify. Bought it used with 130,000 from dealership. After only 1 month, randomly my windows and door locks started repeatedly rolling up and down and locking and unlocking without the key even in ignition. Then EPC light came on while driving and went into limp mode. Basic OBD reader said TPS. I read some forums, went to a salvage yard, got the exact model throttle body and replaced it myself. I did a "throttle body adaptation" I had read for throttle to relearn. Started great, EPC went off, has run great since. Until 3 months ago. Intermittently, EPC would come on but go away. It was still driving fine too. I then noticed on my instrument panel that where the mileage would usually show, it now had the message "ERR" but only while car was moving. I'd stop and it would show normal mileage. Then randomly the car just shut off while I was driving, and the "battery" warning symbol illuminated. Had a friend jumped my car and it started right up. (And I will say ever since I've had the car, if I left the switch on ACC to listen to radio, with in 10 minutes, the battery was drained) couple weeks later as driving, I felt the car struggling and then EPC light and check engine light illuminate and back in limp mode. Made it to auto store to scan and got
290- active MIL wheel speed sensor
P0122 -permanent TPS/Acc Pedal Position Sensor
1314-active engine control module. Since I got the car to the house. It's crank/no start. Is it because I swapped batteries without keeping a voltage to it and it needs reset? Or do I literally need a new ECM and have that programmed? I do not have access to VagCom. I just know I have very "random" warning lights, I can't hear the fuel pump anymore and my fans come on when the ignition switch is turned "on". And today my dash lights intermittently go in and out as I move the position of my steering wheel. Any help is greatly appreciated. And if possible, in DIY terms please. I'm decent with working on vehicles but can't figure this one out. Thanks!

-Replaced wheel speed sensors, accelerator pedal, and spark plugs.
Do you
have the same problem?
Yes
No
Saturday, November 12th, 2022 AT 8:05 AM

1 Reply

Tiny
BORIS K
  • EXPERT
Hello,

P1314-no communication with ECM.

First, I would suggest to check all fuses responsible for power supply to the ECM.
Pins 3+5, red/green wire
See image below.

How to check fuses:
https://www.2carpros.com/articles/how-to-check-a-car-fuse

How to use a voltmeter:
https://www.2carpros.com/articles/how-to-use-a-voltmeter

Also check that you have good ground at pins 1+2, brown wire.

This fault could have been caused by a possible discharged battery being jumped.

Cheers, Boris

Was this
answer
helpful?
Yes
No
Monday, November 14th, 2022 AT 5:51 AM

Please login or register to post a reply.

Sponsored links