P1635 FRom ABS light??????

[rjs281]

Can the abs light cause this code? The light only comes on sometimes,thought it was a sensor but my brother-in-law checked my codes with his computer and thats the code it showed.

 

[wmburns]

Do you have different tire sizes (diameter) on the back from the front? The front/back tire diameters have to be within a certain percentage of each other (8% I think). If too much difference, the ABS sensors think that the wheels are slipping because of the the different sizes.

Do you have a custom tune? How about a different axle ratio or non-stock tire diameters?

An yes, the P1635 DTC would be related to ABS problems.

P1635 - Tire/Axle Ratio Out Of Acceptable Range

This Diagnostic Trouble Code (DTC) indicates the tire and axle information contained in Vehicle ID block (VID) does not match vehicle hardware.

Incorrect tire size
Incorrect axle ratio
Incorrect VID configuration parameters

Using the scan tool, view the tire and axle parameters within the VID. They must match vehicle hardware.

 

[rjs281]

Thanks for the info. That must be it. I have a chip,but maybe i should switch to a tuner. Can i adjust for tire size with that? 295/35 back and 245/40 front.

 

[wmburns]

This problem is more than simply programming the PCM with the correct tire size. Because of the size difference between front/rear, the axles are rotating at different speeds. Further, the ABS system assumes the front/rear tires are the same diameter (the PCM does not have the ability to specifiy different diameters for the front/rear).

Maybe someone else can chime in on exactly how much of a mis-match ABS will accept. I thought it is 5-8 percent.