Inspection Procedure

Check ECU-IG fuse.
PREPARATION:

Remove the ECU-IG fuse from instrument panel junction block No.1.

Fig 1: Removing ECU-IG Fuse From Instrument Panel Junction Block No. 1
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK:

Check continuity of ECU-IG fuse.

OK:
1. Continuity
1. NG : Check for short in all the harness and components connected to ECU-IG fuse.
2. OK : Go To Next Step.
Check voltage between terminals B and GND of cruise control ECU connector.
PREPARATION:
1. Remove the ECU with connector still connected.
2. Turn ignition switch ON.
CHECK:

Measure voltage between terminals B and GND of ECU connector.

Fig 2: Measuring Voltage Between Terminals B & GND
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:
1. 10 - 14 V
1. OK : Proceed to next circuit inspection shown on problem symptom table (See PROBLEM SYMPTOMS TABLE ).
2. NG : Go To Next Step.
Check resistance between terminal GND of cruise control ECU connector and body ground.
CHECK:

Measure resistance between terminal GND of ECU connector and body ground.

Fig 3: Measuring Resistance Between Terminal GND & Body Ground
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:
1. Resistance: Below 1 Ω
1. NG : Repair or replace harness or connector.
2. OK : Check and repair harness and connector between cruise control ECU and battery (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).