FixVault

Test Description

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

  1. 2:  This simple test will isolate the problem to the fuse-brake light switch-splice 301 area or the splice 301-EBCM area.
  2. 4:  This is the 1st step in identifying an open, a short to ground, a short to voltage, or a faulty brake light switch.
  3. 12:  This step begins the process of finding an open, a defective connector, or a faulty EBCM.
Step Action Values Yes No
Schematic Reference:  ABS Schematics  
Connector End View Reference:  ABS Connector End Views  
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
Step on the brake pedal.
Do the brake lights come on at all?
- Go to Step 4  Go to Step 3 
3 Remove your foot from the brake pedal.
Do the lights stay on continuously?
- Go to Step 9  Go to Step 12 
Inspect fuse EF13 in the engine compartment fuse block.
Is fuse EF13 open?
- Go to Step 5  Go to Step 7 
5
  1. Replace fuse EF13.
  2. Inspect the new fuse.
Is the new fuse open?
- Go to Step 6  Go to Step 8 
6
  1. Repair the short to ground in the brake light circuitry.
  2. Install a new fuse EF13.
Did you complete the action?
- Go to Step 17  -
7 Repair the open in the brake light switch circuit OG/BK from terminal 6 of connector C102 at the engine fuse block to the brake light switch and circuit L-BU from terminal 11 of splice S301.
Did you complete the repair?
- Go to Step 17  -
8 Inspect for functioning of the brake lights and the antilock brake system (ABS) system.
Did you complete the action?
- Go to Step 17  -
9 Inspect the brake lamp switch adjustment. Refer to Stop Lamp Switch Adjustment .
Did the switch adjustment correct the condition?
- Go to Step 11  Go to Step 10 
10 Replace the brake lamp switch.
Did you complete the repair?
- Go to Step 17  -
11 Repair the short to positive in the circuit YE between the brake light switch, splice S301, the brake lights, the center high-mounted stop lamp, and the ABS wiring harness connector at the electronic brake control module (EBCM) terminal 14.
Did you complete the repair?
- Go to Step 17  -
12 
  1. Disconnect the EBCM connector.
  2. Use a digital voltmeter (DVM) to measure voltage between pins 14 and 19 of the ABS harness connector at the EBCM.
  3. Have an assistant step on the brake pedal.
Does the voltage measure within the specified range?
11-14 V Go to Step 14  Go to Step 13 
13
  1. Examine the connection between the ABS harness connector and the EBCM connector terminals 14 and 19.
  2. Examine the connection at terminal 1 of connector C110.
  3. Examine the wiring of circuit L-BU between splice S301 and terminal 14 of the ABS EBCM connector for an open condition.
  4. Examine the wiring between ground G106 and terminal 19 of the ABS EBCM connector.
  5. Repair the broken wire or the defective connector terminal, or replace the connector, the wiring harness as required.
Did you complete the repair?
- Go to Step 17  -
14 Inspect the interface between the ABS EBCM connector and the EBCM.
Is there damage at the interface?
- Go to Step 15  Go to Step 16 
15 Repair the connector or replace the wiring harness or the ABS unit as required.
Did you complete the repair?
- Go to Step 17  -
16 Replace the ABS unit.
Did you complete the replacement?
- Go to Step 17  -
17
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
- Go to Step 2  System OK