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Pinpoint Test B (IDM Failure Code 212)

  1. With ignition off, connect ICM diagnostic cable to Breakout Box (BOB) and ICM module. DO NOT connect VR sensor tee or coil tee. Use ICM "6" overlay. Connect negative and positive leads of ICM diagnostic cable to battery. Set ICM diagnostic cable box switch to 4/6 CYLINDER position. Set DVOM on 20-volt AC scale. Start engine. Measure voltage between IDM DETECTOR (30) and BAT- (7) of diagnostic cable Ignition Diagnostic Monitor (IDM) at BOB. If pulses are present, IDM detector output will be 5-7 volts AC. If AC voltage is 5-7 volts, go to next step. If AC voltage is not 5-7 volts, go to step 3).
  2. With ignition off, ICM module and PCM disconnected, disconnect ICM module from ICM module tee, leaving ICM diagnostic cable connected to vehicle harness connector. Set DVOM on 200-ohm scale. Connect PCM Breakout Box (BOB) to PCM harness connector. Measure resistance between IDM E (41) at BOB and terminal No. 4 at PCM BOB. If resistance is less than 5 ohms, IDM signal at PCM is okay. PCM does not respond to IDM signal. Replace PCM. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below. If resistance is 5 ohms or more, IDM is open. Check connections and/or repair open circuit or replace harness. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below.
  3. With ignition off and IDM circuit disconnected, set DVOM on 20-volt AC scale. Push ICM IDM button at ICM diagnostic cable connector to BOB. Start engine, and measure voltage between diagnostic cable IDM DETECTOR (30) and BAT- (7) at BOB. If AC voltage is 5-7 volts, go to next step. If AC voltage is not 5-7 volts, IDM output from ICM module does not exist. Replace ICM module. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below.
  4. With ignition off and PCM disconnected, set DVOM on 20-volt AC scale. Crank engine, and measure voltage between diagnostic cable IDM DETECTOR (30) and BAT- (7) at BOB. If voltage is less than 5 volts, go to next step. If voltage is 5 volts or more, PCM is loading IDM signal. Replace PCM. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below.
  5. With ignition off and ICM module and PCM disconnected, disconnect ICM module from diagnostic cable module tee, leaving ICM diagnostic cable connected to vehicle harness connector. Set DVOM on 20-k/ohm scale. Measure resistance between IDM E (41) and BAT- (7) at BOB. If resistance is 10-k/ohms or more, go to next step. If resistance is less than 10-k/ohms, IDM is shorted low. Check connections and/or repair short circuit or replace harness. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below.
  6. With ignition off and ICM module and PCM disconnected, set DVOM on 20-volt DC scale. With Key On Engine Off (KOEO), measure voltage between IDM E (41) and BAT- (7) at BOB. If DC voltage is .5 volt or more, IDM is shorted high. Check connections and/or repair short circuit or replace harness. Remove test equipment, and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES articles in the ENGINE PERFORMANCE section below.
  7. If voltage is less than .5 volt, IDM is shorted to another wire between ICM module and PCM. Check connections and/or repair short circuit or replace harness. Remove test equipment and reconnect all components. Clear continuous memory codes, and rerun QUICK TEST. See QUICK TEST in appropriate G - TESTS W/ CODES article in the ENGINE PERFORMANCE section below.
CAUTION: Unless directed otherwise, DO NOT connect PCM to Breakout Box (BOB) when performing ICM diagnostics.
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