Bad Ccrm?

JustMan

Member
May 5, 2017
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Hello I've recently been having problems with my 2004 mustang gt. The car was working fine until about 2 days ago the car just dies out while driving. I did notice that when it dies out while driving it shows dashes (---) on the mileage. When I try to start it back up it sometimes makes a buzzing noise coming from the CCRM. What I usually have to do to get it to start up again is disconnect the negative from the battery for a few minutes. I've checked all the grounds on the car and they seem to be all good. I am wondering if the CCRM is bad and if I should replace it?
 
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A CCRM is kind of an expensive part to swap for trouble shooting purposes. If this were my car I would confirm the CCRM ground before replacing anything. The ground starts from the radiator core support and goes down around the battery and is a larger black wire with a white stripe. It connects to a round single pin connector. Make sure the connector is fully inserted and clean.

The same applies the the battery terminals and the ground connectors around the radiator core support.

Next perform a visual inspection of the CCRM connector. Look for evidence of overheating. Clean the connector with electrical contact cleaner and re-grease with di-electric grease.

IMO the odds do favor a bad CCRM but there is a possibility this could be:
  • a bad ignition switch
  • a problem with fuse F2.34
  • a wiring fault affecting the CCRM pilot duty circuit.
If you want to rule out a problem in the pilot duty circuit get an "add a fuse" to create an easy way to monitor fuse F2.34 with a VOM or test light. What you are looking for is a voltage drop in the circuit when the problem occurs.

If the voltage drops suspect a problem with the electrical ignition switch. Note, the ignition switches do wear out and can be replaced by a DIY'er. It does NOT require PATS to be reprogrammed.

1999-2004 fuse panel schedule:
http://www.allfordmustangs.com/foru...r-swap-wont-fire-please-help.html#post2669271
 
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A CCRM is kind of an expensive part to swap for trouble shooting purposes. If this were my car I would confirm the CCRM ground before replacing anything. The ground starts from the radiator core support and goes down around the battery and is a larger black wire with a white stripe. It connects to a round single pin connector. Make sure the connector is fully inserted and clean.

The same applies the the battery terminals and the ground connectors around the radiator core support.

Next perform a visual inspection of the CCRM connector. Look for evidence of overheating. Clean the connector with electrical contact cleaner and re-grease with di-electric grease.

IMO the odds do favor a bad CCRM but there is a possibility this could be:
  • a bad ignition switch
  • a problem with fuse F2.34
  • a wiring fault affecting the CCRM pilot duty circuit.
If you want to rule out a problem in the pilot duty circuit get an "add a fuse" to create an easy way to monitor fuse F2.34 with a VOM or test light. What you are looking for is a voltage drop in the circuit when the problem occurs.

If the voltage drops suspect a problem with the electrical ignition switch. Note, the ignition switches do wear out and can be replaced by a DIY'er. It does NOT require PATS to be reprogrammed.

1999-2004 fuse panel schedule:
http://www.allfordmustangs.com/foru...r-swap-wont-fire-please-help.html#post2669271
okay after cleaning all the grounds and cleaning the round single pin connector with electric contact cleaner and applying di-electric grease i haven't had the problem occur. Now I'm having an idle issue. The idle surges from what looks like 700 to 1000 and then sometimes dies out. I've replaced the iac and cleaned the MAF sensor but still have the same issue. I've checked all the vac lines and they are all fine I checked the TB and it is clean. The idle surges when i come to a stop and sometimes dies out. To start the car after it dies i have to put it in neutral or it wont even turn. Any idea what it could be? Here a video of what it does :
View: https://youtu.be/gIIWir0Wxhc
 
Has the alternator and battery been tested? We want to make sure the battery holds a charge and the alternator's output is good without excessive AC ripple (bad diode).

What is the voltage at the battery when this problem occurs?

How long has it been since the battery was reconnected? Trying to make sure the PCM has had enough time to re-learn new idle trim values.

Is the AC on? Is the AC low on Freon?
 
Has the alternator and battery been tested? We want to make sure the battery holds a charge and the alternator's output is good without excessive AC ripple (bad diode).

What is the voltage at the battery when this problem occurs?

How long has it been since the battery was reconnected? Trying to make sure the PCM has had enough time to re-learn new idle trim values.

Is the AC on? Is the AC low on Freon?

The battery was changed out not to long ago. When the problem occurs I get 13.27/13.29 volts with lights on and radio on no AC. I've disconnected battery for a few minutes after changing the IAC and cleaning the MAF. I got the IAC from o'reilly's I did notice when i first put it on I was getting a hanging high idle and then it would drop down to normal after a while i started to get this surging idle. The AC is off when the problem occurs and haven't had a chance to check if it is low on Freon. I also noticed that when the radiator fan kicks on the rpms drop lower I'm not sure if that's normal.
 
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What about the alternator? Been tested yet? The voltage seems just a little on the low side to me. Is the voltage above 14 with no ACC on?

Regardless this does not rule out a bad alternator diode or worn out slip ring. Don't cut corners here. The test is free at almost any auto Parts store

Here's some information about how to save some $$ rebuilding your own alternator.

https://www.stangnet.com/mustang-forums/threads/higher-amp-alternator-how-much-higher.897392/

The work done has changed the symptoms. So at least at some level you were in the area of the problem.

Has the PCV valve been replaced? Or at the least been cleaned?

If we are unable to find a "simple" common cause the list of "possible" causes gets much more difficult. Examples include:
  • un-equal power balance/weak cylinder (ignition, fuel, or base motor).
  • Timing chain ware or broken timing chain guides allowing unstable cam timing.
  • bad cam sensor (not very likely).
  • EVAP problem. Stuck partially open VMV or Large EVAP leak.
  • Base motor problem (compression test).
  • Some kind of electrical problem that comes/goes. Loose wire. Bad ground. More tests needed.
 
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What about the alternator? Been tested yet? The voltage seems just a little on the low side to me. Is the voltage above 14 with no ACC on?

Regardless this does not rule out a bad alternator diode or worn out slip ring. Don't cut corners here. The test is free at almost any auto Parts store

Here's some information about how to save some $$ rebuilding your own alternator.

https://www.stangnet.com/mustang-forums/threads/higher-amp-alternator-how-much-higher.897392/

The work done has changed the symptoms. So at least at some level you were in the area of the problem.

If we are unable to find a "simple" common cause the list of "possible" causes gets much more difficult. Examples include:
  • un-equal power balance/weak cylinder (ignition or base motor).
  • Timing chain ware or broken timing chain guides allowing unstable cam timing.
  • bad cam sensor (not very likely).
  • Base motor problem (compression test).
  • Some kind of electrical problem that comes/goes. Loose wire. Bad ground. More tests needed.
So I got 13.99 volts again with radio on and lights on. Then i got 13.16 volts with the AC, radio, and lights on. So then i tried just the AC on it own and i got 13.90 volts again i did notice when the radiator fan kicks on it drains some power and brings down the volts a bit. I'm going to get the alternator tested soon.
 
What about the alternator? Been tested yet? The voltage seems just a little on the low side to me. Is the voltage above 14 with no ACC on?

Regardless this does not rule out a bad alternator diode or worn out slip ring. Don't cut corners here. The test is free at almost any auto Parts store

Here's some information about how to save some $$ rebuilding your own alternator.

https://www.stangnet.com/mustang-forums/threads/higher-amp-alternator-how-much-higher.897392/

The work done has changed the symptoms. So at least at some level you were in the area of the problem.

Has the PCV valve been replaced? Or at the least been cleaned?

If we are unable to find a "simple" common cause the list of "possible" causes gets much more difficult. Examples include:
  • un-equal power balance/weak cylinder (ignition, fuel, or base motor).
  • Timing chain ware or broken timing chain guides allowing unstable cam timing.
  • bad cam sensor (not very likely).
  • EVAP problem. Stuck partially open VMV or Large EVAP leak.
  • Base motor problem (compression test).
  • Some kind of electrical problem that comes/goes. Loose wire. Bad ground. More tests needed.
Okay the alternator tested good at the parts store where I bought the IAC from. The guy said I might have gotten a faulty IAC since it's free to swap it out I'm gonna give it a try. How long should I leave the battery disconnected after changing out the IAC?