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Pinpoint Test B

  1. Check IDM Signal At EDIS Module - With key off, install EDIS diagnostic cable to BOB, and EDIS module. Do not connect VR sensor tee or coil tees. Use EDIS 8 overlay (if available). Connect EDIS diagnostic cable, negative and positive leads to battery. Set EDIS diagnostic cable box switch to "8 cylinder" position. Set DVOM on 20-volt AC scale. Start engine and measure voltage between diagnostic cable IDM detector (30) and BAT- (7) at BOB. If input voltage pulses are present at IDM detector, output will be a square wave 5-7 volt AC signal. If output signal is correct, go to step 2. If signal is not correct, go to step 3.
  2. Check For IDM Open Circuit - With key off, disconnect EDIS module from module tee. Leave EDIS diagnostic cable connected to vehicle harness connector. Set DVOM on 200-ohm scale. Measure resistance between IDM E (41) at BOB and terminal No. 4 at ECA vehicle harness connector. If resistance is 5 ohms or less, replace ECA. IDM pulse at ECA is okay. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If resistance is greater than 5 ohms, repair open circuit. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  3. Check IDM Output From EDIS Module, Isolate Harness - With key off, set DVOM on 20-volt AC scale. Push EDIS IDM button at the EDIS diagnostic cable connector to breakout box (if available). Start engine and measure voltage between IDM detector (30) and BAT- (7) at BOB. If AC voltage is 5-7 volts, go to step 4. If voltage is not 5-7 volts, replace EDIS module. There is no IDM output from module. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  4. Check for IDM Short In ECA, Isolate ECA - With key off, disconnect ECA. Set DVOM on 20-volt AC scale. Crank engine and measure voltage between IDM detector (30) and BAT- (7) at BOB. If AC voltage is 4.5-6.0 volts, replace ECA. ECA is loading IDM signal. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If voltage is not 4.5-6.0 volts, go to step 5.
  5. Check For IDM Short To Ground In Harness - With key off, disconnect EDIS diagnostic cable positive lead to battery. Disconnect the EDIS module from EDIS module tee, leave EDIS diagnostic cable connected to vehicle harness connector. Set DVOM on 200-ohm scale. Measure resistance between IDM E (41) and BAT- (7) at BOB. If resistance is less than 5 ohms, service or repair short circuit. IDM is shorted to ground. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
  6. Check For IDM Short To Power In Harness - With key off, set DVOM on 20-volt DC scale. With KOEO, measure voltage between IDM E (41) and BAT- (7) at BOB. If DC voltage is greater than 0.5 volt, service short circuit. IDM is shorted to VBAT between EDIS module and processor. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test. If DC voltage is 0.5 volt or less, service short circuit or replace harness. IDM is shorted to another wire between EDIS module and ECA. Remove all test equipment and reconnect all components. Clear Continuous Memory Codes and rerun Quick Test.
WARNING: DO NOT connect ECA to EDIS diagnostic cable. The 60-pin connector on this harness may be connected to a Breakout Box (BOB) only. Never connect ECA to BOB when performing EDIS diagnostics.
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