I have a 1999 flareside with drum rear and disc front with 4.6 l v8 and anti lock brakes.

I get abs error code C 1230 and the code returns when I clear it. I notice no braking degradation. and once I clear the error the vehicle can travel 20 to 30 miles before it returns. Once the vehiocle shuts off and is restarted the light goes out and comes back in 10 to 20 to 30 miles.

I believe the codes correlate to rr rear brakes circuit faiure, I also checked the cable going to the rear differential for proper connection! Any suggestions

 

C1230 Rear Anti-Lock Brake Sensor (Electrical/Static) ABS GO to Pinpoint Test I.

I1 CHECK FOR FAULT REPEATABILITY


NGS



Clear Continuous DTCs

Drive the vehicle at least 16 km/h (10 mph).

Retrieve and document continuous DTCs.


Is DTC C1230 retrieved?
Yes
GO to I2.

No
If no DTCs are retrieved, GO to I6 .

If a different DTC is retrieved. GO to ABS Control Module Diagnostic Trouble Code (DTC) Index.
I2 CHECK ANTI-LOCK BRAKE SENSOR COIL RESISTANCE AT EHCU CONNECTOR


Connect EEC-IV 60-Pin Breakout Box.

Measure the resistance between EEC-IV 60-Pin Breakout Box pin 9, circuit 523 (RD/PK) and pin 21, circuit 519 (LG/BK).


Is the resistance between 800 and 3500 ohms?
Yes
GO to I4.

No
If the resistance is below 800 ohms, INSTALL a new rear anti-lock brake sensor. REFER to Sensor—Rear. CLEAR the DTCs. DRIVE the vehicle over rough road and through a car wash. REPEAT the self-test.

If the resistance is greater than 3500 ohms, GO to I3 .
I3 DETERMINE LOCATION OF FAULT


Rear Anti-Lock Brake Sensor C414


Measure the resistance between the rear anti-lock brake sensor pin 1 and pin 2.


Is the resistance greater than 3500 ohms?
Yes
REPLACE the rear anti-lock brake sensor. REFER to Sensor—Rear.

No
REPAIR circuit 519 (LG/BK) and circuit 523 (RD/PK).
I4 CHECK REAR ANTI-LOCK BRAKE SENSOR CIRCUIT FOR SHORT TO GROUND

Measure the resistance between EEC-IV 60-Pin Breakout Box pin 9, circuit 523 (RD/PK) and ground; and between EEC-IV 60-Pin Breakout Box pin 21, circuit 519 (LG/BK) and ground.


Are the resistances greater than 10,000 ohms?
Yes
GO to I6.

No
GO to I5.
I5 CHECK FOR ANTI-LOCK BRAKE SENSOR SHORT


Rear Anti-Lock Brake Sensor C414


Measure the resistance between rear anti-lock brake sensor pin 1 and ground; and between rear anti-lock brake sensor pin 2 and ground.


Are the resistances greater than 10,000 ohms?
Yes
REPAIR circuit 519 (LG/BK) and circuit 523 (RD/PK). CLEAR the DTCs. DRIVE the vehicle over rough road and through a car wash. REPEAT the self-test.

No
INSTALL a new rear anti-lock brake sensor; REFER to Sensor—Rear. CLEAR the DTCs. DRIVE the vehicle over rough road and through a car wash. REPEAT the self-test.
I6 TEST FOR INTERMITTENT ANTI-LOCK BRAKE SENSOR FAULT
Carry out the Sensor Failure test for the rear anti-lock brake sensor. REFER to Component Test — Intermittent Failures.


Did the rear anti-lock brake sensor pass?
Yes
RECONNECT the rear anti-lock brake sensor C414. CLEAR the DTCs. DRIVE the vehicle over rough road and through a car wash. REPEAT the self-test.

No
REPAIR as necessary. CLEAR the DTCs. DRIVE the vehicle over rough road and through a car wash. REPEAT the self-test.