Diagnosis Procedure

ICC BRAKE SWITCH


Diagnosis Procedure

1.CHECK OVERALL FUNCTION-I
With CONSULT-III
1. Turn ignition switch ON.
2. Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT-III.
3. Check "BRAKE SW1" indication under the following conditions.





Without CONSULT-III
1. Turn ignition switch ON.





2. Check voltage between ECM terminal 108 and ground under the following conditions.





OK or NG
OK - INSPECTION END
NG - GO TO 2.
2.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.





2. Disconnect ICC brake switch harness connector.
3. Turn ignition switch ON.





4. Check voltage between ICC brake switch terminal 1 and ground with CONSULT-III or tester.

Voltage: Battery voltage

OK or NG
OK - GO TO 6.
NG - GO TO 3.
3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.





2. Disconnect ICC brake hold relay.
3. Check harness continuity between ICC brake switch terminal 1 and ICC brake hold relay terminal 3. Refer to Wiring Diagram

Continuity should exist.

OK or NG
OK - GO TO 4.
NG - Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK ICC BRAKE HOLD RELAY POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.





2. Check the voltage between ICC brake hold relay terminal 4 and ground with CONSULT-III or tester.

Voltage: Battery voltage

OK or NG
OK - GO TO 8.
NG - GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors M31, E152
- Fuse block (J/B) connector M4
- 10 A fuse (No.15)
- Harness for open or short between ICC brake hold relay and fuse
- Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108, ICC brake switch terminal 2 and ICC unit terminal 29.
Refer Wiring Diagram.

Continuity should exist.

4. Also check harness for short to ground and short to power.
OK or NG
OK - GO TO 7.
NG - Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK ICC BRAKE SWITCH
ICC Brake Switch.
OK or NG
OK - GO TO 10.
NG - Replace ICC brake switch.
8.CHECK ICC BRAKE HOLD RELAY POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ICC brake hold relay terminal 1 and ICC unit terminal 47, ICC brake hold relay terminal 2 and ground. Refer to Wiring Diagram

Continuity should exist

2. Also check harness for short to ground or short to power in harness or connectors.
OK or NG
OK - GO TO 9.
NG - Repair or replace.
9.CHECK ICC BRAKE HOLD RELAY
ICC Brake Switch.
OK - GO TO 10.
NG - Replace ICC brake hold relay.
10.CHECK INTERMITTENT INCIDENT
How to Check Terminal and Intermittent Incident.
- INSPECTION END