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Diagnostic Aids

Typical causes for DTC C1102 to set:

Weak or discharged battery
Poor battery terminal contact
Excessive battery draws from factory or after-market equipment parasitic load.
Poor battery ground at block or chassis
Poor terminal contact at the EBCM
Poor EBCM ground connection
Charging system malfunction generator

Thoroughly inspect the wiring and the connectors. Failure to inspect the wiring and the connectors carefully and fully can cause replacement of parts without repairing the malfunction.

DTC C1102

Step	Action	Values	Yes	No
1	Did you perform the Diagnostic System Check - ABS?	-	Go to Step 2	Go to Diagnostic System Check - ABS
2	Disconnect the electronic brake control module (EBCM) connector. Turn the ignition switch ON. Check the voltage between the terminal 4 and 8 of the EBCM connector. Check the voltage between the terminal 4 and 24 of the EBCM connector. Were the voltages within the specified range?	9.4-17 V	Go to Step 3	Go to Step 4
3	Replace the EBCM. Refer to Brake Modulator Assembly Replacement . Check again the diagnostic circuit. Did you find any problem?	-	Go to Step 1	System OK
4	Check the battery voltage between the positive and negative terminals of the battery. Was the voltage within the specified range?	9.4-17 V	Go to Step 6	Go to Step 5
5	Replace the battery. Refer to Battery and Battery Tray Replacement .	-	Go to Step 1	-
6	Check the resistance between terminal 4 of the EBCM connector and the terminal (+) of the battery. Does the resistance measure less than the specified value?	1 Ω	Go to Step 8	Go to Step 7
7	Check both the terminals mentioned in step 6. Repair the terminals, as needed. Check the EBCM connector and wiring harness. Repair or replace the wiring harness as needed. Did you find and correct the condition?	-	System OK	-
8	Check the resistance between the terminal 8, 24 and G104. Does the resistance measure less than the specified value?	1 Ω	Go to Step 10	Go to Step 9
9	Repair or replace the EBCM connector or G104. Did you complete the repair?	-	Go to Step 1	-
10	Connect a voltmeter to the positive and negative terminal of the battery. Turn OFF all accessories. Start the engine. Monitor the voltage on the meter with the engine running at 2,000 RPM for several seconds. And also check the voltage between the terminal 4 and 8. And also check the voltage between the terminal 4 and 24. Do the voltages measure less than the specified value?	17 V	Go to Step 1	Go to Step 11
11	Repair the alternator. Did you complete the repair?	-	Go to Step 1	-