Diagnostic Aids

WARNING: This page is about a different car, the 2008 Suzuki Swift +, 2008 Pontiac Wave, and 2008 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.

Typical causes of no communication with the EBCM:

Poor terminal contact at the EBCM
Loss of EBCM ground to terminal 8 and 24
Loss of battery voltage at EBCM terminals 9 and/or 25
Loss of ignition voltage at EBCM 4
Open/grounded data line
Data line with high resistance

Step	Action	Value(s)	Yes	No
1	Did you perform the Diagnostic System Check - Vehicle?	-	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Turn the ignition switch OFF. Disconnect the electronic brake control module (EBCM) harness. Connect a voltmeter to the EBCM harness terminal 9 and then to body ground. Does the voltage measure within the specified range?	B+	Go to Step 4	Go to Step 3
3	Repair the source of the low voltage to terminal 9. Inspect for an open fuse, poor terminal contact, or a grounded wire. Did you find and correct the condition?	-	System OK	-
4	Connect a voltmeter to the EBCM harness terminal 25 and then to the body ground. Does the voltage measure within the specified range?	B+	Go to Step 6	Go to Step 5
5	Repair the source of the low voltage to terminal 25. Inspect for an open fuse, poor terminal contact, or a grounded wire. Did you find and correct the condition?	-	System OK	-
6	Turn ON the ignition switch. Connect a voltmeter to the EBCM harness terminal 4 and then to body ground. Does the voltage measure within the specified range?	B+	Go to Step 8	Go to Step 7
7	Repair the source of the low voltage to terminal 4. Inspect for an open fuse, poor terminal contact, or a grounded wire. Did you find and correct the condition?	-	System OK	-
8	Turn the ignition switch OFF. Connect an ohmmeter to the EBCM harness terminal 8 and 24 and then to body ground. Does the resistance measure less than the specified value?	2 Ω	Go to Step 10	Go to Step 9
9	Repair the source of the high resistance between terminal 8 and 24. Find and inspect the ground location where the circuit is secured to body ground. Did you find and correct the condition?	-	System OK	-
10	Turn OFF the ignition switch. Verify the EBCM harness is still disconnected from the EBCM. Connect an ohmmeter to the EBCM harness terminal 7 and the data link connector (DLC) terminal 7. Does the resistance measure less than the specified value?	2 Ω	Go to Step 12	Go to Step 11
11	Repair the source the high resistance between terminal 7 and DLC terminal 7. Did you complete the repair?	-	System OK	-
12	Turn the ignition switch OFF. Verify the EBCM harness is still disconnected. Connect an ohmmeter to the EBCM harness terminal 7 and then to body ground. Does the resistance measure OL, open circuit?	-	Go to Step 14	Go to Step 13
13	Find and repair the short to ground on the data line. Did you find and correct the condition?	-	System OK	-
14	Replace the EBCM. Did you complete the replacement?	-	System OK	-