Inspection Procedure

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Check voltage between terminal IDH of A/C amplifier and body ground.
PREPARATION: Remove the center cluster module control with connectors still connected.

Check
1. Turn ignition switch ON.
2. Turn light control switch OFF.
3. Turn rear defogger switch OFF.
4. Measure voltage between terminal IDH of A/C amplifier.
  OK: Voltage: Below 1.0 V.
  
  Fig 1: Locating A/C Amplifier Terminal IDH (Connector Installed)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. OK: Proceed to next circuit inspection shown on problem symptoms table. See PROBLEM SYMPTOMS TABLE .
2. NG: Go to step 2.
Check voltage between terminal IDH of A/C amplifier and body ground.
PREPARATION: Disconnect the connector from A/C amplifier.

Check
1. Turn ignition switch ON.
2. Turn light control switch OFF.
3. Turn rear defogger switch OFF.
4. Measure voltage between terminal IDH of A/C amplifier on wire harness side connector.
  OK: Voltage: Below 1.0 V.
  
  Fig 2: Locating A/C Amplifier Terminal IDH (Connector Removed)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. OK: Check and replace A/C amplifier.
2. NG: Go to step 3 .
Check harness and connector between A/C amplifier and converter . See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION .
1. NG: Repair and replace harness and connector.
2. OK: Check and replace converter.