Bora V5 - An EPC light, low voltage

[BMCR42]

Summary: V5 Bora with an occasional no-start, an EPC light, 10 or so low voltage codes across multiple modules and other more notable ABS (01314 ECM - Check DTC Memory), Instrument (00562 & 00779 Oil level & outside air temp sensor open or short to plus) and AUTO HVAC (00281 Vehicle Speed Sensor Faulty) and AUTO HVAC (01274 - Air Flow Flap Positioning Motor Faulty) codes. Fuses have been checked, the battery has been charged and reconditioned, and spark plugs, ignition coils and throttle body have been replaced.

Hello, I recently picked up a 2003 VW Bora V5 with 220k km’s. I was aware of a potential issue with the battery in which the car wouldn't start when unlocked for a while until jumpstarted. The battery voltage presented happy (It held 12.4V over days and didn’t drop below 9V on crank (Until it didn’t) so I left it temporarily.

After an aggressive engine bay hosing and throttle body cleaning it developed a misfire. Then during a test drive the EPC light came on which made me limp the car back home while engine power slowly dropped off until it could barely manage 50kph. I then acquired a scanner and was greeted with a litany of codes seen in SCAN 1

I imagined the EPC light may have been a damaged TB (Apparently you shouldn’t actuate A DBW TB), so I swapped in a replacement used one, along with new ignition coils and spark plugs which got rid of the misfire(s), however the EPC light persisted along with many other codes. I used a CTEK battery charger to recondition and charge the battery, checked all fuses and, as side point, the wiring to an O2 sensor had melted causing a short, so these were disconnected temporarily, leaving us with the range of codes seen here in SCAN 2

The central locking and windows appear to work fine despite the codes however the radio is dead, and a relay can be heard clicking at around 100bpm. What is going on here? What should be the first move? Could I have done some kind of water damage? Is a new battery really the answer? RAHHHHH!

SCAN 2

VCDS-Lite
Windows Based VAG/VAS Emulator
Version: Release 1.2
www.Ross-Tech.com
Workshop Code: 000 00000
Self-Diagnosis Log
Wednesday, 30 April 2025, 12:47:25:22121
VIN Number: WVWZZZ1JZ4W026642 License Plate:
Mileage: Repair Order:
Chassis Type: 1J - VW Golf/Bora IV
Scan: 01,02,03,08,15,16,17,19,22,29,35,36,37,39,46,47,55,56,57,75,76
-------------------------------------------------------------------------------
Address 01: Engine Labels: Redir Fail!
Controller: 066 906 032 AJ
Component: MOTRONIC ME7.1 G 0002
Coding: 00031
Shop #: WSC 01266
VCID: 5BC94206DA3D
WVWZZZ1JZ4W026642 VWZ7Z0C7917584
1 Fault Found:
18042 - Accelerator Position Sensor 2 (G185): Signal too High
P1634 - 35-00 - -
Readiness: 0110 1101
-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 1C0-907-37x-ASR.LBL
Controller: 1C0 907 379 K
Component: ASR FRONT MK60 0103
Coding: 0021505
Shop #: WSC 01266
VCID: 3217CFA2ED37
1 Fault Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 3Bx-907-044.LBL
Controller: 3B1 907 044 C
Component: CLIMATRONIC C 2.0.0
Coding: 11000
Shop #: WSC 01266
VCID: 213530EEB8D1
4 Faults Found:
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent
01206 - Signal for Duration of Ignition Off Time
37-10 - Faulty - Intermittent
00281 - Vehicle Speed Sensor (G68)
37-10 - Faulty - Intermittent
01274 - Air Flow Flap Positioning Motor (V71)
37-00 - Faulty
-------------------------------------------------------------------------------
VCDS-Lite
Self-Diagnosis Log
Wednesday, 30 April 2025, 12:47:25:22121
Page 2
VIN Number: WVWZZZ1JZ4W026642 License Plate:
Address 15: Airbags Labels: 6Q0-909-605-VW5.LBL
Controller: 1C0 909 605 A
Component: 27 AIRBAG VW51 01 0008
Coding: 12855
Shop #: WSC 01266
VCID: 22373FE2BDD7
1 Fault Found:
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent
-------------------------------------------------------------------------------
Address 17: Instruments Labels: 1J0-920-xx5-17.LBL
Controller: 1J5 920 826 A
Component: KOMBI+WEGFAHRSP VDO V20
Coding: 07722
Shop #: WSC 00000
VCID: 2C2BD1DACF13
WVWZZZ1JZ4W026642 VWZ7Z0C7917584
3 Faults Found:
00562 - Sensor for Oil Level/Temperature (G266)
30-10 - Open or Short to Plus - Intermittent
00779 - Outside Air Temp Sensor (G17)
30-10 - Open or Short to Plus - Intermittent
01176 - Key
07-10 - Signal too Low - Intermittent
-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels: 6N0-909-901-19.LBL
Controller: 6N0 909 901
Component: Gateway K<->CAN 0001
Coding: 00006
Shop #: WSC 01266
VCID: F09385AAA3BB
No fault code found.
-------------------------------------------------------------------------------
VCDS-Lite
Self-Diagnosis Log
Wednesday, 30 April 2025, 12:47:25:22121
Page 3
VIN Number: WVWZZZ1JZ4W026642 License Plate:
Address 46: Central Conv. Labels: 1C0-959-799.LBL
Controller: 1C0 959 799 B
Component: 23 Komfortgerát HLO 0003
Coding: 00258
Shop #: WSC 10500
VCID: 361FF3B2015F
10 Faults Found:
01330 - Central Control Module for Central Convenience (J393)
53-10 - Supply Voltage Too Low - Intermittent
00849 - S-contact at Ignition/Starter Switch (D)
25-10 - Unknown Switch Condition - Intermittent
01331 - Door Control Module; Driver Side (J386)
53-10 - Supply Voltage Too Low - Intermittent
01331 - Door Control Module; Driver Side (J386)
37-00 - Faulty
01332 - Door Control Module; Passenger Side (J387)
53-10 - Supply Voltage Too Low - Intermittent
01359 - Internal Central Locking Switch; Passenger Side (E198)
27-10 - Implausible Signal - Intermittent
01333 - Door Control Module; Rear Left (J388)
53-10 - Supply Voltage Too Low - Intermittent
00930 - Locking Module for Central Locking; Rear Left (F222)
27-10 - Implausible Signal - Intermittent
01334 - Door Control Module; Rear Right (J398)
53-10 - Supply Voltage Too Low - Intermittent
00931 - Locking Module for Central Locking; Rear Right (F223)
27-10 - Implausible Signal - Intermittent
End --------------------------------------------------------------------------------------------

 

[PetrolDave]

What should be the first move?

Post an Auto-Scan so we can see the details and how your Bora is configured

 

[BMCR42]

Post an Auto-Scan so we can see the details and how your Bora is configured

Scans are google drive links in the description, wasn't sure if this is an incorrect way to do it. I've attached scan 2 to the bottom.

 

[PetrolDave]

Scans are google drive links in the description, wasn't sure if this is an incorrect way to do it. I've attached scan 2 to the bottom.

Scans should always be embedded as text using code tags - as you have now done (but preferably not using the print function as that's harder to read).

 

[Uwe]

EPC Light due to:

18042 - Accelerator Position Sensor 2 (G185): Signal too High
P1634 - 35-00 - -

How about clearing out the faults codes from all the modules that have them? A lot of them are flagged "Intermittent", meaning the fault condition that set the code did not exist or could not be detected at the time the scan was performed. Doing that will get a better signal-to-noise ratio.

Also, please do not use the [Print] function in VCDS to post data here. The formatting it produces is intended for a sheet-fed printer, but it's much harder to read here than the native text that VCDS produces. That native text can be had using the [Copy] button in VCDS, or by opening any of the .txt files in your Logs or Scans sub-folder with Notepad and then copying the data to paste here.

-Uwe-