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Home >> Ford >> 1992 >> Probe GL, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests - EEC-IV >> EDIS System (Escort & Tracer - 1.9L) >> Pinpoint Test B: Code 188 Or 212

Pinpoint Test B: Code 188 Or 212

  1. Check For IDM Signal At EDIS Module  With ignition off, connect EDIS diagnostic cable to breakout box and EDIS module. DO NOT connect VR sensor tee. Use EDIS "4" overlay on breakout box. Connect EDIS diagnostic cable negative and positive leads to battery. Set EDIS diagnostic cable box switch to 4/6 CYLINDER position. Set DVOM on 20-volt AC scale. Start engine and measure voltage between J30 (diagnostic cable IDM DETECTOR) and J7 (BAT-) at breakout box. If AC voltage is 5-7 volts, go to step 2). If voltage is not 5-7 volts, go to step 3).
  2. Check For IDM Open  With ignition off, disconnect ECA. Disconnect EDIS module from EDIS module tee. Leave EDIS diagnostic cable connected to vehicle harness connector. Connect a second breakout box to ECA harness connector. Set DVOM on 200-ohm scale. Measure resistance between J41 (IDM E) at EDIS breakout box and pin No. 4 at ECA breakout box. If resistance is less than 5 ohms, ECA does not respond to IDM input. Replace ECA. If resistance is 5 ohms or greater, repair short in IDM circuit.
  3. Check IDM Output From EDIS Module  With ignition off, set DVOM on 20-volt AC scale. Push and hold down EDIS IDM button at EDIS diagnostic cable connector (this opens IDM circuit to ECA). Start engine and measure voltage between J30 (diagnostic cable IDM DETECTOR) and J7 (BAT-) at breakout box. If AC voltage is greater than 5 volts, go to step 4). If voltage is 5 volts or less, replace EDIS module (no IDM output from module).
  4. Check For IDM Short In ECA (ECA Disconnected)  With ignition off, disconnect ECA. Crank engine and measure voltage between J30 (diagnostic cable IDM DETECTOR) and J7 (BAT-) at breakout box. If AC voltage is greater than 5 volts, replace ECA. If voltage is 5 volts or less, go to step 5).
  5. Check For IDM Short To Ground In Harness  With ignition off, ensure ECA is disconnected. Disconnect EDIS module from diagnostic cable module tee. Leave EDIS diagnostic cable connected to vehicle harness connector. Set DVOM on 20-k/ohm scale. Measure resistance between J41 (IDM E) and J7 (BAT-) at breakout box. If resistance is greater than 10,000 ohms, go to step 6). If resistance is 10,000 ohms or less, IDM is shorted to ground. Repair short.
  6. Check For IDM Short To VBAT In Harness  With ignition off, ensure EDIS module and ECA are disconnected. Set DVOM on 20-volt DC scale. With ignition on and engine off, measure voltage between J41 (IDM E) and J7 (BAT-) at breakout box. If voltage is less than 0.5 volt, IDM is shorted to another wire between EDIS module and ECA. Repair short circuit or replace harness. If voltage is 0.5 volt or greater, IDM is shorted to VBAT. Repair short.
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