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Home >> Ford >> 1990 >> Bronco II RWD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Test Km - WAC & A/C Demand Switch >> Test Km: Step 6

Test Km: Step 6

6) Check WAC Circuit For Short to Ground  Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector and WAC relay or A/C fan controller. Inspect for and repair any damaged wiring. Install breakout box, leaving ECA disconnected. Set DVOM on 200-k/ohm scale. Measure resistance between WAC circuit at WAC relay or A/C fan controller and chassis ground. If resistance is greater than 10 k/ohms, go to next step for A/C fan controller systems or step 9) for WAC relay systems. If resistance is less than 10 k/ohms, repair short, reconnect all components and recheck system operation.