Diagnostic code
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
If this above measurement fails, you will have to measure the resistance of the coil in the relay. It would be the terminals (terminals 85&86) the above wires connect to. See if the relay coil is open, should probably measure less than 100 ohms (or so).
I would also assume when you start the car up the air pump does not run for the 2 minutes....true?
Last edited by pcolt94; Oct 7, 2019 at 01:06 PM.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Check fuse 21 which is the ENG 2 fuse to see if it is open.
Do this next as indicated above.
"Is there 12 Volts on the small pnk/blk wire to ground with the key=ON? If = NO, the code will set".
Then;
Tap into the brown wire to measure the voltage. Turn key on, there should be 12 volts there. Then start engine, the voltage should go low near 0 (zero) volts for 2 minutes. Then it should go back to 12 volts.
This is normal operation and should tell you what is going on at the point the PCM is looking at.
Do this next as indicated above.
"Is there 12 Volts on the small pnk/blk wire to ground with the key=ON? If = NO, the code will set".
Then;
Tap into the brown wire to measure the voltage. Turn key on, there should be 12 volts there. Then start engine, the voltage should go low near 0 (zero) volts for 2 minutes. Then it should go back to 12 volts.
This is normal operation and should tell you what is going on at the point the PCM is looking at.
Last edited by pcolt94; Oct 8, 2019 at 10:16 AM.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
One minute is enough time to clear codes by removing the battery cable in module 1 (CCM) and module 4 (PCM). It just won't clear the code for module 9 (brake computer), you have to use on the on board diagnostic system or scan tool (Tech 1 or 2) but we are not talking about that with this problem. So code 29 in module 4 is the PCM.
Disconnecting the battery will clear the H and C codes in module 4 as well as module 1.
Disconnecting the battery will clear the H and C codes in module 4 as well as module 1.
Thread Starter
Cruising
Joined: May 2009
Posts: 10
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One minute is enough time to clear codes by removing the battery cable in module 1 (CCM) and module 4 (PCM). It just won't clear the code for module 9 (brake computer), you have to use on the on board diagnostic system or scan tool (Tech 1 or 2) but we are not talking about that with this problem. So code 29 in module 4 is the PCM.
Disconnecting the battery will clear the H and C codes in module 4 as well as module 1.
Disconnecting the battery will clear the H and C codes in module 4 as well as module 1.
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Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
This will give you the data to proceed in the correct direction.