Charge System Fault
Thread Starter
Instructor
Joined: Oct 2014
Posts: 129
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From: Brandon MS
Charge System Fault
Can anyone help steer me in the right direction for this: I keep getting the following two messages when I start the car
(1)Charging System Fault
(2)Service Vehicle Soon
Also the only two codes I have after driving the car yesterday are:
1637H and C
1638H and C
I know both codes are historical AND current
I do not know what triggers the "Service Vehicle Soon" message.
I have checked my battery voltage at 14.0 and this alternator was recently replaced by the previous owner (I have the receipt). I guess it could already be bad but doesn't seem likely. Am I missing something to check or is there something going on that could be easily fixed that I am missing? I just bought the car so I'm still learning a lot but have a loooong way to go. Thanks for any help!!
(1)Charging System Fault
(2)Service Vehicle Soon
Also the only two codes I have after driving the car yesterday are:
1637H and C
1638H and C
I know both codes are historical AND current
I do not know what triggers the "Service Vehicle Soon" message.
I have checked my battery voltage at 14.0 and this alternator was recently replaced by the previous owner (I have the receipt). I guess it could already be bad but doesn't seem likely. Am I missing something to check or is there something going on that could be easily fixed that I am missing? I just bought the car so I'm still learning a lot but have a loooong way to go. Thanks for any help!!
Thread Starter
Instructor
Joined: Oct 2014
Posts: 129
Likes: 0
From: Brandon MS
I promise I have read about this before I posted this asking for help.
Definitely a TON of information about this. I was hoping that with the passage of time that there would be some fresh information about what to do to "cure" this issue. I have been reading as much as I can and, as I've stated before, I'm a new owner and trying to learn as much as possible. If I read some of these threads right, it looks as though the only "real" cure for this is to buy an OEM alternator/generator from the stealorship for big bucks and install it so the PCM is happy again, or just live with these DIC messages. Again, there is so much information out there that I feel like I get "lost" just searching for something that will correct the issue with my 2001 A4 coupe.....I'm just trying to see if there is anything out there that will steer me in the right direction, not just any direction. Thanks again.
Definitely a TON of information about this. I was hoping that with the passage of time that there would be some fresh information about what to do to "cure" this issue. I have been reading as much as I can and, as I've stated before, I'm a new owner and trying to learn as much as possible. If I read some of these threads right, it looks as though the only "real" cure for this is to buy an OEM alternator/generator from the stealorship for big bucks and install it so the PCM is happy again, or just live with these DIC messages. Again, there is so much information out there that I feel like I get "lost" just searching for something that will correct the issue with my 2001 A4 coupe.....I'm just trying to see if there is anything out there that will steer me in the right direction, not just any direction
. Thanks again.
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
The alternator interface with the PCM appears fairly typical but the PCM throws the stupid messages when a replacment regulator doesn't have the same timing as the stock one as it first energizes.
The message is thrown when the regulator doesn't switch the "light" circuit to 12V when the engine is started or if the field PWM feedback goes too low or too high (no field or full field). I think the stock regulator ramps-on and the PCM watches for that.
There are parts for the stock alternators and you can also get complete rebuilds or new from Ebay.
A tuner can also get rid of the fault by disabling the terminal monitoring in the system settings. I would first try disabling the PWM feedback terminal and see if it goes away. If not, disable the "light" terminal. Worst case, if you disable both the alternator still works fine but you'd have to watch the volt meter to ensure it's working.
The message is thrown when the regulator doesn't switch the "light" circuit to 12V when the engine is started or if the field PWM feedback goes too low or too high (no field or full field). I think the stock regulator ramps-on and the PCM watches for that.
There are parts for the stock alternators and you can also get complete rebuilds or new from Ebay.
A tuner can also get rid of the fault by disabling the terminal monitoring in the system settings. I would first try disabling the PWM feedback terminal and see if it goes away. If not, disable the "light" terminal. Worst case, if you disable both the alternator still works fine but you'd have to watch the volt meter to ensure it's working.
Thread Starter
Instructor
Joined: Oct 2014
Posts: 129
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From: Brandon MS
Newest Drama for Codes
I just changed my oil AND my spark plugs (what a PITA!!) and now my newest code is: 10-PCM 0118 and I noticed that my temp gauge is pegged high. WTH?? Also, my new battery voltage as reported on my DIC is 13.5 - 13.6 and just yesterday it was 14.1 steady. The battery is a new Duracell and my Fluke multimeter reads 12.7 on the terminals. The 1637 & 1638 are still there....
What the heck did I mess up to get the 0118 code? Is there something I might've knocked loose while doing the plug change? I'll say this: it was definitely a PITA and I've never had to fight that hard to get to plugs. (I put in Bosch Double Platinum and put anti-sieze on them too). The old plugs were Denso copper types.
Anybody have any good info about the new 0118 ECT all of a sudden? I'm sure the 1637 & 1638 are not gone either, they just didn't show this time when I drove it around the block. Oh, and my check engine light comes on but clears when I clear the 0118 code but comes right back with the code so I've messed up something.....
What the heck did I mess up to get the 0118 code? Is there something I might've knocked loose while doing the plug change? I'll say this: it was definitely a PITA and I've never had to fight that hard to get to plugs. (I put in Bosch Double Platinum and put anti-sieze on them too). The old plugs were Denso copper types.
Anybody have any good info about the new 0118 ECT all of a sudden? I'm sure the 1637 & 1638 are not gone either, they just didn't show this time when I drove it around the block. Oh, and my check engine light comes on but clears when I clear the 0118 code but comes right back with the code so I've messed up something.....
Drifting
Joined: Feb 2005
Posts: 1,869
Likes: 61
From: montreal quebec
I just changed my oil AND my spark plugs (what a PITA!!) and now my newest code is: 10-PCM 0118 and I noticed that my temp gauge is pegged high. WTH?? Also, my new battery voltage as reported on my DIC is 13.5 - 13.6 and just yesterday it was 14.1 steady. The battery is a new Duracell and my Fluke multimeter reads 12.7 on the terminals. The 1637 & 1638 are still there....
What the heck did I mess up to get the 0118 code? Is there something I might've knocked loose while doing the plug change? I'll say this: it was definitely a PITA and I've never had to fight that hard to get to plugs. (I put in Bosch Double Platinum and put anti-sieze on them too). The old plugs were Denso copper types.
Anybody have any good info about the new 0118 ECT all of a sudden? I'm sure the 1637 & 1638 are not gone either, they just didn't show this time when I drove it around the block. Oh, and my check engine light comes on but clears when I clear the 0118 code but comes right back with the code so I've messed up something.....
What the heck did I mess up to get the 0118 code? Is there something I might've knocked loose while doing the plug change? I'll say this: it was definitely a PITA and I've never had to fight that hard to get to plugs. (I put in Bosch Double Platinum and put anti-sieze on them too). The old plugs were Denso copper types.
Anybody have any good info about the new 0118 ECT all of a sudden? I'm sure the 1637 & 1638 are not gone either, they just didn't show this time when I drove it around the block. Oh, and my check engine light comes on but clears when I clear the 0118 code but comes right back with the code so I've messed up something.....
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
Check the wires going to the solenoid. Basically, get under it and take apart the wires on the main post of the solenoid and clean them before re-installing them. You likely pushed them around when changing plug #8.
As for the temperature, check the sensor on the drivers side head at the front.
As for the temperature, check the sensor on the drivers side head at the front.
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Thread Starter
Instructor
Joined: Oct 2014
Posts: 129
Likes: 0
From: Brandon MS
Now, to find the charging gremlin.....
Thread Starter
Instructor
Joined: Oct 2014
Posts: 129
Likes: 0
From: Brandon MS
Check the wires going to the solenoid. Basically, get under it and take apart the wires on the main post of the solenoid and clean them before re-installing them. You likely pushed them around when changing plug #8.
As for the temperature, check the sensor on the drivers side head at the front.
As for the temperature, check the sensor on the drivers side head at the front.
