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IG Power Source Circuit

  1. Remove A/C-heater control assembly, leaving harness connectors connected. See A/C-HEATER CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. Turn ignition on. Backprobe between terminals A21-2 (Light Green/Red wire) and A21-22 (White/Black wire) of A/C-heater control assembly connector. See Figure.
  2. If battery voltage exists, no problem is indicated at this time. If battery voltage does not exist, turn ignition off. Check continuity between A/C-heater control assembly connector terminal A21-22 (White/Black wire) and ground. If continuity exists, go to next step. If continuity does not exist, repair wiring between terminal A21-22 (White/Black wire) and body ground.
  3. Inspect HEATER fuse (10-amp), located in instrument panel fuse block. If fuse is okay, inspect wiring harness and connectors between A/C-heater control assembly and battery. Repair as necessary. If fuse is blown, replace fuse and inspect for short circuit.
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