Ignition coils not firing?

2004 VOLKSWAGEN PASSAT
150,000 MILES • 1.8L • 4 CYL • TURBO • 2WD • AUTOMATIC
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JOSHMODE2
My ignition coils are not firing because P0685 it will crank but will not start and I checked the ignition coils and they're not firing I found that the fuel pump relay was bad so I changed it thinking that was it and it still won't start I changed all the fuses now all I have left is a relays but I have no manual showing what relays go where and what relays or what because I lost my owner's manual and I don't have the money to afford Haynes manual.
Aug 5, 2025 at 3:55 PM
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STEVE W.
  • ✓ASE Certified Mechanic
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How about we do a bit of testing first? Grab a cheap test light and find fuse 29 in the panel on the left side of the dash. Turn on the key and probe the two tabs on the back of that fuse. There should be power there. If there isn't then the next stop is the fuel pump relay, pull it and look for power on terminal 17 That should have power full time. If you have power, there then find the power supply relay in the box next to the ECM. Pull it and check for power on terminals 2 and 9. If you have power there then put the relays back in. Then go to the ECM itself. Look for power on terminal 62. If you have power, there but still nothing the ECM might be the issue because that is the power to the ECM.
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Aug 5, 2025 at 7:45 PM
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JOSHMODE2
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Thank you, I will try that and let you know.
Aug 6, 2025 at 6:54 AM
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STEVE W.
  • ✓ASE Certified Mechanic
  • 15,171 POSTS
  • ASE Certified Mechanic
We will be waiting.
Aug 6, 2025 at 11:25 AM
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JOSHMODE2
  • MEMBER
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I need help cuz my ignition coils are not firing and I don't know why and I can't figure it out I replaced all the fuses I see relays but I don't have owners manual to tell me which ones are which so I can't check them I don't know how to check it in please help me thank you
Aug 6, 2025 at 2:05 PM (Merged)
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STEVE W.
  • ✓ASE Certified Mechanic
  • 15,171 POSTS
  • ASE Certified Mechanic
REF - https://www.2carpros.com/questions/ignition-coils-not-fine
Aug 6, 2025 at 2:06 PM (Merged)
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