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DTC Troubleshooting

DTC DIAGNOSTIC TROUBLESHOOTING CHART

Step Action YES NO
1  Was "Engine and Emission Control System" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2  DTC check 
  1. Check DTC of ECM, TCM and BCM.

Is there any DTC(s) (other than DTC U0001 and DTC B1156)? 		 Go to applicable DTC diag. flow. Go to Step 3.
3  Circuit check 
  1. Turn OFF ignition switch.
  2. Disconnect connectors from ECM and BCM.
  3. Check for proper connection to ECM and BCM at applicable terminals.
  4. If OK, measure resistance between "E61-32" terminal of ECM connector and "G53-9" terminal of BCM connector, between "E61-33" terminal of ECM connector and "G53-1" terminal of BCM connector.

Is each resistance 1 Ω or less? 		 Go to Step 4. "WHT" wire circuit (between "E61-32" terminal of ECM connector and "G53-9" terminal of BCM connector) or "RED" wire circuit (between "E61-33" terminal of ECM connector and "G53-1" terminal of BCM connector) open or high resistance.
4  Circuit check 
  1. Disconnect connectors from TCM.
  2. Check for proper connection to TCM at applicable terminals.
  3. If OK, measure resistance between "E61-32" terminal of ECM connector and "G07-1" terminal of TCM connector, between "E61-33" terminal of ECM connector and "G07-2" terminal of TCM connector.

Is each resistance 1 Ω or less? 		 Go to Step 5. "WHT" wire or "RED" wire in shorted to power circuit.
5  Circuit check 
  1. Measure resistance between "G07-1" terminal of TCM connector and "G53-9" terminal of BCM connector, between "G07-2" terminal of TCM connector and "G53-1" terminal of BCM connector.

Is each resistance 1 Ω or less? 		 Go to Step 6. "WHT" wire circuit (between "G07-1" terminal of TCM connector and "G53-9" terminal of BCM connector) or "RED" wire circuit (between "G07-2" terminal of TCM connector and "G53-1" terminal of BCM connector) open or high resistance.
6  Circuit check 
  1. Turn ignition switch to ON position.
  2. Measure voltage between "E61-32" terminal of ECM connector and vehicle body ground, between "E61-33" terminal of ECM connector and vehicle body ground.

Is each voltage 0 - 1 V? 		 Go to Step 7. "WHT" circuit or "RED" circuit shorted to power supply line.
7  Circuit check 
  1. Turn ignition switch to OFF position.
  2. Measure resistance between "E61-32" terminal of ECM connector and vehicle body ground, between "E61-33" terminal of ECM connector and vehicle body ground.

As they infinite? 		 Go to Step 8. "WHT" circuit or "RED" circuit shorted to ground.
8  Circuit check 
  1. Measure resistance between "E61-32" and "E61-33" terminals of ECM connector.

Is it infinite? 		 Go to Step 9. "WHT" circuit is shorted to "RED" circuit.
9  Do you have oscilloscope?  Go to Step 10. Substitute a known-good BCM and recheck. If malfunction is detected, substitute a known-good TCM and recheck. If malfunction is detected, substitute a known-good ECM and recheck.
10  Waveform range check 
  1. Connect connectors to ECM, TCM and BCM.
  2. Connect oscilloscope between "E61-32" terminal of ECM connector and ground, between "E61-33" terminal of ECM connector and ground.
  3. Check if each range of two waveforms is as specified in illustration below.
G04721018

Is it in good condition? 		 Go to Step 13. Go to Step 11.
11  Waveform range check 
  1. Disconnect connectors from BCM.
  2. Connect oscilloscope between "E61-32" terminal of ECM connector and ground, between "E61-33" terminal of ECM connector and ground.
  3. Check if each range of two waveforms is as specified in illustration below.
G04721019

Is it in good condition? 		 Substitute a known-good BCM and recheck. Go to Step 12.
12  Waveform range check 
  1. Disconnect connectors from TCM.
  2. Connect connectors to BCM.
  3. Connect oscilloscope between "E61-32" terminal of ECM connector and ground, between "E61-33" terminal of ECM connector and ground.
  4. Check if each range of two waveforms is as specified in illustration below.
G04721020

Is it in good condition? 		 Substitute a known-good TCM and recheck. Substitute a known-good ECM and recheck.
13  Communication check 
  1. Disconnect connector from ECT sensor.
  2. Start engine for 1 minute or more.
  3. Check DTC of TCM referring to DTC CHECK .

Is DTC U0001 indicated? 		 Go to Step 14. Substitute a known-good ECM and recheck.
14  Communication check 
  1. Connect connector to ECT sensor.
  2. Disconnect connector from input shaft speed sensor.
  3. Perform "DTC Confirmation Procedure" referring to DTC P0717 (NO.14): INPUT / TURBINE SPEED SENSOR CIRCUIT NO SIGNAL
  4. Check DTC for ECM referring to DTC CHECK .

Is DTC U0001 indicated? 		 Substitute a known-good BCM and recheck. Substitute a known-good TCM and recheck.
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