Connect the scan tool to the data link connector(DLC) and start the engine
Wait 3 seconds and check the DTC
IS THERE DTC P1603 ?
YES
Repair open or short in the wire between the ECM terminal 10/C230-1 and the TCM terminal 3/C224-3.
Repair open or short in the wire between the ECM terminal 9/C230-1 and the TCM terminal 4/C224-1.
Go to step 4
NO
Intermittent failure, system is O.K at this time.
Go to step 4
Turn the ignition switch OFF and start the engine
Perform the test drive on the lift
Check the signal waveform of CAN high side between the the ECM terminal 10/C230-1 and the TCM terminal 3/C224-3. and check the signal waveform of CAN low side between the ECM terminal 9/C230-1 and the TCM terminal 4/C224-1.
IS THERE THE SIGNAL WAVEFORM DISPLAYED PROPERLY ?
YES
Make sure there is no the DTC in the dignostic trouble codes menu
NO
Replace a known - good ECM and recheck. If the CAN signal waveform is displayed, replace the ECM.
Replace a known - good TCM and recheck. If the CAN signal waveform is displayed, replace the TCM.
Go to step 7
WAVEFORM ANALYSIS
This test should be inspected after depressing the HOLD mode while idling. In this CAN communication signal waveform, it is impossible to read through by displaying the scantool If unstable waveform pattern with non-uniform frequency or no signal, replace the ECM or the TCM after checking the wiring harness.
MONITORING FOR PENDING DTC SET ?
YES
Go to the applicable troubleshooting procedure.
NO
System is O.K
