C1253

DTC C1253: ICCS2 Data Link Right Malfunction (Part 1 Of 2):

DTC C1253: ICCS2 Data Link Right Malfunction (Part 2 Of 2):

DTC C1253 Schematic:

CIRCUIT DESCRIPTION
The CVRSS calculates normal force and transmits a PWM signal to the EBTCM via two dedicated data lines, one right, and one left. The EBTCM uses this information to detect rough road conditions and allows for more aggressive braking on rough surfaces.

CONDITION FOR SETTING THE DTC
The EBTCM measures the PWM duty cycle sent from the CVRSS and checks to see that it is between 10% and 90%. The possible values of duty cycle are 20%, 40%, 60%, and 80%. The CVRSS sends each value twice therefore any normal force value sent to the EBTCM should match either the previous or next normal force value. If either of the above faults are present for more than 5 seconds out of any 10 second period the EBTCM will set a normal force fault.

ACTION TAKEN WHEN THE DTC SETS
A malfunction DTC is stored and the rough road performance enhancements of ICCS do not function. ABS/TCS/ICCS are still functional.

CONDITIONS FOR CLEARING THE DTC
Condition for DTC is no longer present and scan tool clear DTC function is used. Fifty start cycles have passed with no DTCs detected.

DIAGNOSTIC AIDS
It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.

TEST DESCRIPTION
The numbers below refer to step numbers on the diagnostic table.
3. Checks the PWM duty cycle.
5. Checks for short to B+ in CKT 961.


7. Checks for short to ground in CKT 961.
9. Checks for open in CKT 961.