Test Description

The numbers below refer to the step numbers on the diagnostic table.

2: This step uses the scan tool to check the battery positive voltage circuit to the EBCM.
3: This step checks the battery positive voltage supply circuit.

DTC C1237

Step	Action	Value(s)	Yes	No
Schematic Reference: ABS Schematics
1	Did you perform the ABS Diagnostic System Check?	-	Go to Step 2	Go to Diagnostic System Check - ABS
2	Turn OFF all of the accessories. Install a scan tool. Start the engine. Run the engine at approximately 2000 RPM. With a scan tool, observe the Switched Battery Voltage parameter in the ABS data list. Does the scan tool indicate that the switched battery voltage is less than the specified voltage?	17 V	Go to Step 5	Go to Step 3
3	Turn OFF the ignition. Disconnect the EBCM harness connector. Install the J 39700 using the J 39700-99 to the EBCM harness connector only. Start the engine. Run the engine at approximately 2000 RPM. Measure the voltage at the J 39700 between the battery positive voltage circuit of the EBCM and a good ground. Does the voltage measure less than the specified value?	17 V	Go to Step 4	Go to Symptoms - Engine Electrical in Engine Electrical
4	Use the scan tool in order to clear the DTCs. Carefully test drive the vehicle at a speed above 8 km/h (5 mph). Does the DTC reset?	-	Go to Step 5	System OK
5	Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement?	-	Go to Step 6	-
6	Use the scan tool in order to clear the DTCs. Operate the vehicle within the conditions for Running the DTC as specified in the supporting test. Does the DTC reset?	-	Go to Step 2	System OK