Diagnostic Test
- CHECK FOR AN ACTIVE DTC
- With the scan tool, read Transmission Control Module (TCM) DTCs and record on the repair order.
- Record the Event Data and Environmental Data.
- With the scan tool, erase DTCs.
- Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
- With the scan tool, read TCM DTCs.
Did the DTC return?
Yes
- Go To 2
No
- Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
- CHECK FOR ENGINE CHARGING SYSTEM DTCS
- With the scan tool, read Powertrain Control Module (PCM) DTCs.
Are any Engine Charging System DTCs set?
Yes
- Repair Engine Charging System DTCs. Refer to DTC TROUBLESHOOTING .
- Perform the TRANSMISSION VERIFICATION TEST to verify the Transmission and or controller was not damaged. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
No
- Go To 3
- With the scan tool, read Powertrain Control Module (PCM) DTCs.
- CHECK FOR SOLENOID SUPPLY CIRCUIT DTCS
- Refer to the recorded TCM DTCs.
Were any solenoid supply circuit DTCs set?
Yes
- Repair the solenoid supply circuit DTCs. Refer to DTC TROUBLESHOOTING .
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
No
- Go To 4
- Refer to the recorded TCM DTCs.
- CHECK SYSTEM VOLTAGE
- CHECK FOR AN OVERCHARGING CONDITION
- Start the Engine and raise the engine speed to 2, 000 rpm.
- With the scan tool, read the Transmission system voltage for at least 60 seconds.
Does the Transmission system voltage read above 16.9 volts for any period of time?
Yes
- Repair the charging system for an over charging condition. Refer to DIAGNOSIS AND TESTING .
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
No
- Go To 6
- CHECK IF VEHICLE WAS JUMP STARTED WITH 24-VOLT SYSTEM NOTE:
Some Recreational Vehicles (RVs), Buses, and Semi Tractors use 24-volt systems.
- Check if the vehicle was jump started by a vehicle with a 24-volt charging system.
Was the vehicle jump started by a vehicle with a 24-volt charging system?
Yes
- This is the cause of the DTC. Erase the DTC and return the vehicle to the customer.
- Perform the TRANSMISSION VERIFICATION TEST to verify the Transmission and or TCM was not damaged. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
No
- Go To 9
- Check if the vehicle was jump started by a vehicle with a 24-volt charging system.
- CHECK THE TCM POWER SUPPLY CIRCUITS
- Turn the ignition off.
- Disconnect the TCM harness connector.
- Turn the ignition on.
- Using a 12-volt test light connected to ground, check the TCM power supply circuits at the TCM harness connector.NOTE:
The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
- Go To 8
No
- Repair the TCM power supply circuits for an open or high resistance.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
- CHECK THE TCM (Z909) GROUND CIRCUITS
- Ignition ON.
- Using a 12-volt test light connected to B(+), check the (Z909) Ground circuits at the TCM harness connector.
Does the test light illuminate brightly for each Ground circuit?
Yes
- Go To 9
No
- Repair the TCM (Z909) Ground circuit for an open or high resistance.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
- CHECK RELATED HARNESS CONNECTIONS
- Disconnect all TCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
- Proper connector installation.
- Damaged connector locks.
- Corrosion.
- Other signs of water intrusion.
- Weather seal damage (if equipped).
- Bent terminals.
- Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
- Terminals that have been pushed back into the connector cavity.
- Perform a terminal drag test on each connector terminal to verify proper terminal tension.
Repair any conditions that are found.
- Reconnect all TCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
- With the scan tool, read TCM DTCs.
Did the DTC return?
Yes
- Replace the TCM in accordance with the Service information. Refer to MODULE, TRANSMISSION CONTROL (TCM), REMOVAL AND INSTALLATION .
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
No
- Perform the TRANSMISSION VERIFICATION TEST. Refer to 948TE-9HP48 TRANSMISSION VERIFICATION TEST .
- Test complete.