Description

Connector:

DESCRIPTION
Codes C1229, C1260, and C1237 are generated by the anti-lock electronic control module's detection of a missing, erratic, or otherwise improper wheel speed signal from the rear axle wheel speed sensor. The codes are set for specific faults at various vehicle speeds that are as follows:
- Code C1229 - Anti-lock brake control module detects that the rear axle wheel speed information is erratic. This code is only set at vehicle speeds greater than 40 km/h (25 mph).
- Code C1260 - Anti-lock brake control module detects that the rear axle wheel speed information does not match the left front and right front wheel speed information.
- Code 1237 - Anti-lock brake control module detects that the rear axle wheel speed signal has dropped out when it was previously there. This code is not dependent upon vehicle speed.
- Codes C1229, C1260 and C1237 CANNOT be set with the vehicle stationary. The vehicle should be driven when attempting to duplicate the concern. If Codes C1229, C1260 or C1237 are set, then the ABS warning lamp will come on and will remain on until the vehicle is shut off. However, if the condition is corrected, the ABS warning lamp will be turned off by the anti-lock brake control module and the system will again be operational.


POSSIBLE CONTRIBUTING COMPONENT/VEHICLE WIRING CONCERNS
- Damaged/missing tone ring teeth or missing tone ring
- Air gap too small or too large
- Excessive axle vibration
- Weak sensor
- Loose sensor
- Intermittent short or open in Circuit 523 (R/PK) or 519 (LG/BK)

NOTE: If above codes are stored with C1155, check for intermittent short to ground or open. If above codes only are stored, the concern is output related and it is not necessary to check for intermittent open/short conditions.

- Disturbances caused by ignition or Radio Frequency Interference (RFI)
- Defective trigger circuit in anti-lock brake control module