Inspection Procedure

Check operation of stop light .
Check that the stop light lights up when the brake pedal is depressed and turns off when the brake pedal is released.
1. OK: Go to next step .
2. NG: Check stop light circuit. See STOP LIGHT SWITCH CIRCUIT .
Check voltage between terminal STP (48) of Skid Control ECU and body ground .
Disconnect the connector from the Skid Control ECU.

Measure the voltage between terminal 48 of Skid Control ECU harness side connector and body ground when the brake pedal is depressed.

Fig 1: Testing Skid Control ECU Terminal 48 Voltage
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Voltage: 7.5 - 14 V
1. OK: Check and replace Skid Control ECU .
2. NG: Go to next step .
Check for open circuit in harness and connector between terminal STP of Skid Control ECU and stop light switch. See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE .
1. OK: Proceed to next circuit inspection shown in problem symptoms table. See PROBLEM SYMPTOMS .
2. NG: Repair or replace harness or connector .