Pinpoint Test A: DTC B1484 - Brake Pedal Input Open Circuit

CAUTION: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

A1 CHECK THE STOPLAMPS
- Apply the brake pedal while observing the stoplamps.
- Do the stoplamps illuminate?
1. YES : Go to A2.
2. NO : REFER to EXTERIOR LIGHTING article to continue diagnosis of the stoplamps.
A2 CHECK CIRCUIT 810 (RD/LG) FOR AN OPEN
- Key in OFF position.
- Disconnect: ABS Module C135
- Measure the voltage between ABS module C135-30, circuit 810 (RD/LG), harness side and ground while applying the brake pedal.
- Is the voltage greater than 10 volts?
1. YES : Go to A3.
2. NO : VERIFY SJB fuse 18 (10A) is OK. If OK, REPAIR circuit 810 (RD/LG). CLEAR the DTCs. REPEAT the self-test.
A3 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect: ABS Module C135
- Check for:
  - corrosion.
  - pushed-out pins.
  - spread terminals.
- Connect the ABS module connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module . CLEAR the DTCs. REPEAT the self-test.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.