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Conditions For Clearing The DTC

Refer to AUTOMATIC TRANS (AW30-40LS) .

DTC P0700 - CAN-BUS NO COMMUNICATION WITH TRANSMISSION CONTROL MODULE

Step Action Values Yes No
1 Was the "On-Board Diagnostic (OBD-II) System Check" performed? - Go to Step 2 Go to On-Board Diagnostic (OBD-II) System Check
2 Check for poor/faulty connection at the TCM or ECM connector.
If a poor/faulty connection is found, repair as necessary.
Was the problem found?		 - Verify repair Go to Step 3
3 Using the DVM and check the CAN BUS high circuit.
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect the TCM connector and ECM connector.
  3. Check the circuit for open or short to ground circuit.

Was the problem found?		 - Repair faulty harness and verify repair Go to Step 4
4 Using the DVM and check the CAN BUS low circuit.
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect the TCM connector and ECM connector.
  3. Check the circuit for open or short to ground circuit.

Was the problem found?		 - Repair faulty harness and verify repair Go to Step 5
5 Using the DVM and check the CAN BUS high circuit.
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect the TCM connector.
  3. Ignition "ON".
  4. Check the circuit for short to power supply circuit.

Was the problem found?		 - Repair faulty harness and verify repair Go to Step 6
6 Using the DVM and check the CAN BUS high circuit.
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect the TCM connector.
  3. Ignition "ON".
  4. Check the circuit for short to power supply circuit.

Was the problem found?		 - Repair faulty harness and verify repair Go to Step 7
7
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect TCM connector.
  3. Measure the resistance of ECM CAN BUS circuit.
Does the tester indicate standard resistance?		 Approximately 120Ω Go to Step 8 Go to On-Board Diagnostic (OBD-II) System Check
8
  1. Ignition "OFF", Engine "OFF".
  2. Disconnect TCM connector.
  3. Measure the resistance of ECM CAN BUS circuit.
Does the tester indicate standard resistance?		 Approximately 120 Ω Go to Step 9 Go to On-Board Diagnostic (OBD-II) System Check
9 Install the test ECM.
Program the test ECM (Immobilizer system). Refer to IMMOBILIZER SYSTEM .
Check the OBD-II test for following condition:
  1. When the ignition is "ON", turn on the MIL and RPL (RPL is put out after 3 seconds).
  2. When the engine is started.

Did the DTC disappear?		 - Go to Step 10 Go to Step 2
10 Replace the original ECM.
Check the poor connection between the ECM and ECM connector.
Recheck the OBDII test again.
When the engine is started.
Did the DTC disappear?		 - Verify repair Go to Step 11
11 Disconnect the ABS control unit connector.
Reprogramming the original ECM. (Engine control and Immobilizer control)
Recheck the OBDII.
Did the DTC disappear?		 - Verify repair Go to Step 12
12 Replace the ECM.
Recheck the OBDII test again.
Did the DTC disappear?		 - Verify repair Refer to DIAGNOSTIC AIDS 
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