It will crank over but wont start?

Tiny
JOSHMODE2
  • MEMBER
  • 2004 VOLKSWAGEN PASSAT
  • 1.8L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 150,000 MILES
It will crank over but wont start its giving me a P0685 code I replaced all fuses I found the fuel pump relay bad bought a new one and it still did not start I checked if it was getting fire it was not getting fire I dont know what to do can someone please help me thank you
Tuesday, August 5th, 2025 AT 6:24 AM

6 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,610 POSTS
Okay, this code is the clue, we need to check the engine computer fuses and if they are okay change out the relay.

P0685 - ECM/PCM Power Relay Control Circuit/Open

Here is a guide to help you check the fuses, be sure the key is on before testing.

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

Check out the images (below). Let us know how it goes
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Tuesday, August 5th, 2025 AT 10:21 AM
Tiny
JOSHMODE2
  • MEMBER
  • 14 POSTS
I replaced all fuses with new but I dont know where all the relays are I know where some are but I dont have diagram for what they are because I dont have a owners manual or anything
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Tuesday, August 5th, 2025 AT 11:23 AM
Tiny
JOSHMODE2
  • MEMBER
  • 14 POSTS
Ken I cant find where that panel is on my car I cant find it
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Tuesday, August 5th, 2025 AT 12:19 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,610 POSTS
The relay panel and 13-position auxiliary relay panel are located in the driver side footwell, behind the lower instrument panel trim. The 8-position auxiliary relay panel is located just behind the relay panel and 13-position auxiliary relay panel.
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Tuesday, August 5th, 2025 AT 12:50 PM
Tiny
JOSHMODE2
  • MEMBER
  • 14 POSTS
Can you send me a picture of the relays and what they run like the ignition coils and stuff like that cuz I don't know what relay runs the ignition coils cuz they are not firing
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Tuesday, August 5th, 2025 AT 1:12 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,610 POSTS
I can help you but we only handle one problem per thread, please post your new question here, you must be logged in. Lead with "ignition coils are not firing"

https://www.2carpros.com/questions/new

Cheers, Ken
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Tuesday, August 5th, 2025 AT 2:46 PM

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