c-codes

[Parshal]

I discovered a way to find out the c-codes this weekend. Searching the forum here, I see that robobx posted the same thing in this thread



https://www.turbodieselregister.com...s=&threadid=82456&highlight=reading+the+codes



but saw no replies. I also have code A7 and was wondering what it means.



Ideas?

 

[nickleinonen]

i tried that yesterday on my truck to see what lights are in the cluster [i could have swore i saw a red light flicker in the center between tach & speedo] and when the c-codes came up, i had like 6 of them. don't know what they mean, no performance issues with the truck, so i am not worried about it [yet]

 

[ThomasLawrence]

I also have code A7 and was wondering what it means

A7 is a VIN checksum error.



Sounds like someone programmed the wrong VIN into your cluster (there's a check digit in the VIN used for just this purpose)

 

[rbattelle]

I have a complete set of service manuals for the 2003 (Service vol. 1 and 2, Body, Transmission, Powertrain, Chassis). Call me a doofus, but where the heck are you guys finding these C-codes in these manuals!?

 

[Badunit]

Dang, it took me so long to find it someone already answered. Just so I don't feel like I wasted my time, "00" means it's done.



The code numbers are on pg 535 of the body diagnostics manual.



Here's the description of VIN checksum error:



"Set Condition: Once the cluster learns a valid VIN and another VIN is transmitted on the bus. The cluster decodes the VIN that is transmitted on the bus by the PCM. If the VIN is valid the cluster stores the information. If the VIN information does not equate to the encrypted value then the fault is set. "



This is different from a "VIN Previously Stored" error which is set if the VIN transmitted on the bus is different from the VIN programmed into the cluster.

 

[rbattelle]

It's odd that this code would pop up. Seems to me the only way to transmit a new VIN to the instrument clusted is to physically disconnect it and reconnect it to another vehicle. The beginning part of the Body diagnostics manual clearly states that this should never be done, precisely because the mismatch in VIN numbers will confuse the cluster. Apparently, these clusters feature an automated detection of the vehicle they've been installed in when they're first powered on. Connecting them to a different vehicle just confuses the heck out of 'em.