Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read TCM DTCs and record on the repair order.
2. Record the Event Data and Environmental Data.
3. With the scan tool, erase DTCs.
4. 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.
5. With the scan tool, read TCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Go To 9
CHECK FOR ENGINE CHARGING SYSTEM DTCS
1. With the scan tool, read PCM DTCs.
  Are any Engine Charging System DTCs set?
  
  Yes
  - Repair Engine Charging System DTCs. Refer to the DTC INDEX article .
  - Perform the TRANSMISSION VERIFICATION TEST to verify the Transmission and or controller was not damaged. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 3
CHECK FOR SOLENOID SUPPLY CIRCUIT DTCS
1. Refer to the recorded TCM DTCs.
  Were any solenoid supply circuit DTCs set?
  
  Yes
  - Repair the solenoid supply circuit DTCs. Refer to the TRANSMISSION CONTROL MODULE (TCM) - DIAGNOSTIC CODE INDEX article .
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 4
CHECK SYSTEM VOLTAGE
1. Start the Engine.
2. With the scan tool, under transmission, check system voltage.
  Is the transmission system voltage above 9.0 volts?
  
  Yes
  - Go To 5
  No
  - Go To 7
CHECK FOR AN OVERCHARGING CONDITION
1. Start the Engine and raise the engine speed to 2, 000 RPM.
2. With the scan tool, monitor 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 TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  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.
1. 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 TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 9
CHECK THE TCM POWER SUPPLY CIRCUITS
1. Turn the ignition off.
2. Disconnect the TCM harness connector.
3. Turn the ignition on.
4. 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 TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK THE TCM (Z909) GROUND CIRCUITS
1. Ignition ON.
2. 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
  
  NOTE:
  If this Electronic Control Unit (ECU) is being replaced with a new unit, a diagnostic scan tool MUST be used to align the PROXI configuration data into the new ECU. Follow the routine outlined in the diagnostic scan tool for PROXI Configuration Alignment under Body Control Module (BCM) Miscellaneous Functions menu.
  - Using the schematics as a guide, check the Transmission Control Module (TCM) terminals and connectors for corrosion, damage or pushed out terminals. Pay particular attention to the power and ground circuits. If no problems are found, replace the TCM and perform programming and PROXI Configuration Alignment procedures. Refer to MODULE, TRANSMISSION CONTROL, REMOVAL .
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Repair the TCM (Z909) Ground circuit for an open or high resistance.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle the wires while checking for shorted and open circuits.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Test complete.