Battery voltage is supplied to the antilock brake system (ABS) warning lamp with the ignition switch in the ON or START positions. The warning lamp can be activated only by the ABS control module internally supplying ground to terminal 20 or by the shorting bar in the ABS module connector when it is disconnected from the module.
This procedure inspects for a problem in the wiring, a faulty ground, a voltage supply problem, a burned out indicator lamp, or a contact problem in a connector.
• | A fuse has blown. |
• | The indicator lamp has burned out. |
• | There is a corroded or broken connector terminal. |
• | There is a faulty ground connection. |
• | There is a broken wire in a wiring harness. |
• | The electronic brake control module (EBCM) is faulty. |
The numbers below refer to the step numbers on the diagnostic table.
This test verifies an inoperative lamp condition.
This test checks for voltage on the lamp circuit.
This begins a series of tests of the circuit from the indicator lamp to the EBCM and ground.
This begins a series of tests of the voltage supply circuits that power the indicator lamp.
Step | Action | Values | Yes | No |
---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
Does the lamp illuminate for about 4 seconds, then turn OFF? | -- | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | |
With the ignition still ON, observe the oil pressure lamp. Is the oil pressure lamp illuminated? | -- | Go to Step 4 | Go to Step 19 | |
Does the ABS indicator illuminate? | -- | Go to Step 5 | Go to Step 8 | |
5 |
Is there a poor connection at any of these terminals? | -- | Go to Step 6 | Go to Step 7 |
6 | Repair the faulty terminals or replace the EBCM as required. Did you complete the repair? | -- | Go to Step 30 | -- |
7 | Replace the EBCM. Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | -- | Go to Step 30 | -- |
8 |
Is the resistance equal to the specified value? | 0 ohms | Go to Step 10 | Go to Step 9 |
9 | Repair the open or high resistance in the circuit from the EBCM connector, terminal 19 to ground G103. Did you complete the repair? | -- | Go to Step 30 | -- |
10 |
Is the bulb burned out? | -- | Go to Step 11 | Go to Step 12 |
11 |
Did you complete the repair? | -- | Go to Step 30 | -- |
12 | Test the continuity at the IPC connector terminal B1. Does the ohmmeter show the specified value? | 0 ohms | Go to Step 14 | Go to Step 13 |
13 | Repair the contact at the IPC connector terminal B1. Did you complete the repair? | -- | Go to Step 30 | -- |
14 | Inspect the wiring harnesses and the connectors in circuit from the IPC terminal B1 to terminal 20 of the EBCM connector. Does the ohmmeter show the specified value? | ∞ | Go to Step 15 | Go to Step 16 |
15 | Repair the open or high resistance. Did you complete the repair? | -- | Go to Step 30 | -- |
16 | Test for continuity between terminal 19 of the ABS connector and ground G103. Is the ground connection equal to the specified value? | 0 ohms | Go to Step 17 | Go to Step 18 |
17 | Replace the EBCM. Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | -- | Go to Step 30 | -- |
18 | Repair the continuity problem between terminal 19 of the EBCM connector and ground G103. Did you complete the repair? | -- | Go to Step 30 | -- |
Is the fuse open? | -- | Go to Step 20 | Go to Step 21 | |
20 | Replace fuse F10. Did you complete the replacement? | -- | System OK | -- |
21 | Inspect fuse Ef6 in the engine fuse block. Is the fuse open? | -- | Go to Step 22 | Go to Step 23 |
22 | Replace fuse Ef6. Did you complete the replacement? | -- | Go to Step 30 | -- |
23 | Measure the voltage at terminal 2 of the ignition switch connector by backprobing. Does the voltage measure within the specified range? | 11-14 V | Go to Step 25 | Go to Step 24 |
24 |
Did you find and correct the condition? | -- | Go to Step 30 | -- |
25 |
Is the voltage within the specified range? | 11-14 V | Go to Step 27 | Go to Step 26 |
26 | Replace the ignition switch. Did you complete the replacement? | -- | Go to Step 30 | -- |
27 |
Does the ohmmeter show the specified value? | ∞ | Go to Step 28 | Go to Step 29 |
28 | Repair the open or the high resistance. Did you complete the repair? | -- | Go to Step 30 | -- |
29 |
Did you complete the repair? | -- | Go to Step 30 | -- |
30 |
Does the DTC reset? | -- | Go to Step 2 | System OK |