CIRCUIT DESCRIPTION: SEM allows the TCM to request torque reduction from the engine controller. Reducing torque allows quicker shifts with more consistent output torque and reduces clutch temperatures which increases clutch life. When an engine torque rating exceeds certain limits, LRTP is used. This feature limits engine torque in lower ranges to protect the transmission from damage if a stall condition occurs.
ACTION TAKEN WHEN THE DTC SETS: 1. The CHECK TRANS light illuminates. 2. If the TCM and ECM software are not compatible, the transmission is restricted to reverse, neutral, and 3rd range. 3. The TCM forces Variable Modulated Main off. 4. The TCM freezes shift adapts (DNA). 5. The TCM inhibits TCC engagement. 6. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: DTC P0614 may be caused by: 1. Incorrect engine calibration. 2. Incorrect transmission calibration. 3. Engine calibration that does not support all required SAE J1939 SEM/LRTP messages. 4. Communication link problem. 5. Defective TCM.
This DTC sets if attempting to reflash the TCM with the engine running; always reflash with the engine off, ignition ON.
CIRCUIT DESCRIPTION: The TCM is equipped with an internal temperature sensor mounted directly to its circuit board. The TCM will take action to protect against damage from overheat.
ACTION TAKEN WHEN THE DTC SETS: 1. The TCM illuminates the CHECK TRANS light (non-OBD II strategy). 2. The TCM commands OFF all solenoids (SOLOFF). 3. The TCM forces Variable Modulated Main off. 4. The transmission will default to hydraulic state of Neutral, Reverse, 1st, 3rd, 5th. 5. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: Clean the TCM if necessary. Excessive road debris reduces the effectiveness of the heat sink on the TCM and could cause internal temperature to rise.
CIRCUIT DESCRIPTION: The sensor reference voltage diagnostic checks the integrity of the 5 volt reference used to power all of the analog input sensors such as Transmission Fluid Temperature (TFT), Throttle Position Sensor (TPS), and the 6-speed Three-Position switch Interface circuits. DTC P0642 is set when a 5 volt reference circuit voltage is below a calibration voltage for a calibration time period.
ACTION TAKEN WHEN THE DTC SETS: When DTC P0642 is active, the following conditions occur: 1. The CHECK TRANS light is illuminated. 2. DTC is stored in TCM history. 3. Additional DTCs active depending on 5V reference to function normally.
CONDITIONS FOR CLEARING DTC/CHECK TRANS LIGHT: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes forty warm-up cycles without failure.
DIAGNOSTIC AIDS: DTC P0642 can be caused by: 1. Chassis harness wire short to ground, high resistance or open. 2. Broken or defective connector assemblies allowing pushed back pins to short together. 3. Unlocked connectors, missing seal plugs allowing moisture in connectors. 4. Defective 5V sensor, TFT sensor, TPS, 6-Speed Three-Position Switch Interface. 5. Defective TCM.
NOTE: The OEM transmission warranty, or the extended coverage for parts and labor, does not cover the repair or replacement of OEM or bodybuilder-provided components or any external wire harnesses not provided by the OEM.
Before repairing or replacing these components or circuits that caused a transmission issue, always contact the vehicle OEM call center and/or the vehicle OEM or bodybuilder service representative to verify the warranty coverage and proper payment arrangements, arrange an alternate sublet or repair plan (if needed), and get troubleshooting assistance for the repair (such as vehicle schematics, DTC trees, parts assistance, etc).
CIRCUIT DESCRIPTION: The sensor reference voltage diagnostic checks the integrity of the 5 volt reference used to power all of the analog input sensors such as oil temperature, Throttle Position Sensor (TPS), and the 6-speed Three-Position interface circuits. DTC P0643 is set when a 5 volt reference circuit voltage is above a calibrated voltage for a calibrated time period.
ACTION TAKEN WHEN THE DTC SETS: When DTC P0643 is active, the following conditions occur: 1. The CHECK TRANS light is illuminated. 2. DTC is stored in TCM history. 3. Additional DTCs active depending on 5V reference to function normally.
CONDITIONS FOR CLEARING DTC/CHECK TRANS LIGHT: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes forty warm-up cycles without failure.
DIAGNOSTIC AIDS: DTC P0643 can be caused by: 1. Chassis harness wire short to battery. 2. Broken or defective connector assemblies allowing pushed back pins to short together. 3. Unlocked connectors, missing seal plugs allowing moisture in connectors. 4. Defective TCM.
NOTE: The OEM transmission warranty, or the extended coverage for parts and labor, does not cover the repair or replacement of OEM or bodybuilder-provided components or any external wire harnesses not provided by the OEM.
Before repairing or replacing these components or circuits that caused a transmission issue, always contact the vehicle OEM call center and/or the vehicle OEM or bodybuilder service representative to verify the warranty coverage and proper payment arrangements, arrange an alternate sublet or repair plan (if needed), and get troubleshooting assistance for the repair (such as vehicle schematics, DTC trees, parts assistance, etc).
CIRCUIT DESCRIPTION: High Side Driver 1 (HSD1) supplies battery voltage to the Main Modulation, Torque Converter Clutch (TCC) and Pressure Control Solenoid 1 (PCS1) solenoids via wire 111. HSD1 is continuously on during normal operation except during brief circuit tests. The TCM regulates control current to the solenoids by switching the appropriate low side driver on and off. DTC P0657 indicates the TCM has detected multiple low side circuits are open while having HSD1 voltage. DTC P0657 could be caused by open condition in the high side wiring attached to HSD1 (wire 111).
ACTION TAKEN WHEN THE DTC SETS: 1. Main modulation is inhibited. 2. If the failure occurs while in a forward range a shift to 1st, 3rd or 5th range is made. 3. While diagnostic response is active, if the shift selector is moved to N (Neutral), the transmission shifts to neutral; if the shift selector is moved to R (Reverse), the transmission shifts to reverse. If the shift selector is moved to D (Drive) range or R (Reverse) and the transmission is compromised by overspeeding or direction change, the transmission shifts to neutral. 4. The CHECK TRANS light illuminates. 5. The TCM forces variable main mod off. 6. The TCM inhibits TCC engagement. 7. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: The diagnostic tool may be used to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: The following procedures are not documented in any OEM procedures or in any OEM Troubleshooting or Service information and should not be used as a method to diagnose any transmission DTCs, function, or shift quality concern:
1. Back-probing any connections used for transmission features or functions may damage and/or unlock terminals from the back-probed connector creating permanent or intermittent shorts and/or open circuits. If possible, use the J-39700 Breakout Box, the appropriate harness adapters, and appropriate magnetic overlays to troubleshoot the vehicle.
2. Load-testing any transmission-related circuits with any other electrical devices such as vehicle lamps or relays, especially with the TCM connected to the harness. Use J-39700 Breakout Box and appropriate harnesses with the diagnostic tool to monitor the circuit performance in question unless otherwise specified in the various troubleshooting information.
3. Piercing a wire to check for voltages, shorts-to-grounds or other wires anywhere in the circuit but especially at the TCM. This creates a leak path for moisture and damages the wire and insulation.
4. You may have to drive the vehicle in order to experience a fault. Use the data obtained from failure records to determine transmission range and/or certain vehicle operating variables such as temperature and run time. This data can be useful in reproducing the failure mode when the DTC was set.
Inspect the wiring for poor electrical connections at the TCM. Look for the following conditions: 1. A bent terminal. 2. A backed-out terminal. 3. A damaged terminal. 4. Poor terminal tension. 5. A chafed wire. 6. A broken wire inside the insulation.
Inspect OEM wiring harness routing. Look for possible contact points where chafing could occur leading to an open circuit condition. Moving parts on the vehicle could be contacting the harness, such as the parking brake drum, or suspension components.
When diagnosing for an intermittent short or open circuit condition, massage the wiring harness while watching the test equipment for a change.
CIRCUIT DESCRIPTION: High Side Driver 1 (HSD1) supplies battery voltage to the Main Modulation, Torque Converter Clutch (TCC) and Pressure Control Solenoid 1 (PCS1) solenoids via wire 111. HSD1 is continuously on during normal operation except during brief circuit tests. The TCM regulates control current to the solenoids by switching the appropriate low side driver on and off. DTC P0658 indicates the TCM has detected that all solenoids connected to the HSD1 are inactive with a supply voltage in the HSD1 circuit of less than a calibrated value. DTC P0658 indicates a short-to-ground has occurred in the high side wiring attached to HSD1 (wire 111).
ACTION TAKEN WHEN THE DTC SETS: When DTC P0658 is active, the following conditions occur: 1. Variable Modulated Main is inhibited. 2. If the failure occurs while in a forward range a shift to 1st, 3rd or 5th range is made. 3. While diagnostic response is active, if the shift selector is moved to N (Neutral), the transmission shifts to neutral; if the shift selector is moved to R (Reverse), the transmission shifts to reverse. If the shift selector is moved to D (Drive) range or R (Reverse) and the transmission is compromised by overspeeding or direction change, the transmission shifts to neutral. 4. The CHECK TRANS light illuminates. 5. The TCM inhibits TCC engagement. 6. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: The following procedures are not documented in any OEM procedures or in any OEM Troubleshooting or Service information and should not be used as a method to diagnose any transmission DTCs, function, or shift quality concern:
1. Back-probing any connections used for transmission features or functions may damage and/or unlock terminals from the back-probed connector creating permanent or intermittent shorts and/or open circuits. If possible, use the J-39700 Breakout Box, the appropriate harness adapters, and appropriate magnetic overlays to troubleshoot the vehicle.
2. Load-testing any transmission-related circuits with any other electrical devices such as vehicle lamps or relays, especially with the TCM connected to the harness. Use J-39700 Breakout Box and appropriate harnesses with the diagnostic tool to monitor the circuit performance in question unless otherwise specified in the various troubleshooting information.
3. Piercing a wire to check for voltages, shorts-to-grounds or other wires anywhere in the circuit but especially at the TCM. This creates a leak path for moisture and damages the wire and insulation.
4. Debris in the oil pan may allow a shorting condition, causing this DTC to set.
5. HSD1 and HSD2 will reset opening the high side circuit whenever a short-to-ground is detected.
6. You may have to drive the vehicle in order to experience a fault. Use the data obtained from failure records to determine transmission range and/or certain vehicle operating variables such as temperature, and run time. This data can be useful in reproducing the failure mode when the DTC was set.
Inspect the wiring for poor electrical connections at the TCM. Look for the following conditions: 1. A bent terminal. 2. A backed-out terminal. 3. A damaged terminal. 4. Poor terminal tension. 5. A chafed wire. 6. A broken wire inside the insulation.
Inspect OEM wiring harness routing. Look for possible contact points where chafing could occur leading to an open circuit condition. Moving parts on the vehicle could be contacting the harness, such as the parking brake drum, or suspension components.
When diagnosing for an intermittent short or open circuit condition, massage the wiring harness while watching the test equipment for a change.
CIRCUIT DESCRIPTION: High Side Driver 1 (HSD1) supplies battery voltage to the Main Modulation, Torque Converter Clutch (TCC) and Pressure Control Solenoid 1 (PCS1) solenoids via wire 111. HSD1 is continuously on during normal operation except during brief circuit tests. The TCM regulates control current to the solenoids by switching the appropriate low side driver on and off. DTC P0659 indicates the TCM has detected greater than a calibrated value in the HSD1 circuit when HSD1 is OFF during TCM initialization (this indicates that a short to battery exists on the high side circuit 111).
ACTION TAKEN WHEN THE DTC SETS: When DTC P0659 is active, the following conditions occur: 1. Variable Modulated Main is inhibited. 2. If the failure occurs while in a forward range a shift to 1st, 3rd or 5th range is made. 3. While diagnostic response is active, if the shift selector is moved to N (Neutral), the transmission shifts to neutral; if the shift selector is moved to R (Reverse), the transmission shifts to reverse. If the shift selector is moved to D (Drive) range or R (Reverse) and the transmission is compromised by overspeeding or direction change, the transmission shifts to neutral. 4. The CHECK TRANS light illuminates. 5. The TCM freezes shift adapts (DNA). 6. The TCM inhibits TCC engagement. 7. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: The following procedures are not documented in any OEM procedures or in any OEM Troubleshooting or Service information and should not be used as a method to diagnose any transmission DTCs, function, or shift quality concern:
1. Back-probing any connections used for transmission features or functions may damage and/or unlock terminals from the back-probed connector creating permanent or intermittent shorts and/or open circuits. If possible, use the J-39700 Breakout Box, the appropriate harness adapters, and appropriate magnetic overlays to troubleshoot the vehicle.
2. Load-testing any transmission-related circuits with any other electrical devices such as vehicle lamps or relays, especially with the TCM connected to the harness. Use J-39700 Breakout Box and appropriate harnesses with the diagnostic tool to monitor the circuit performance in question unless otherwise specified in the various Troubleshooting information.
3. Piercing a wire to check for voltages, shorts-to-grounds or other wires anywhere in the circuit but especially at the TCM. This creates a leak path for moisture and damages the wire and insulation.
4. You may have to drive the vehicle in order to experience a fault. Use the data obtained from failure records to determine transmission range and/or certain vehicle operating variables such as temperature, and run time. This data can be useful in reproducing the failure mode when the DTC was set.
Inspect the wiring for poor electrical connections at the TCM. Look for the following conditions: 1. A bent terminal. 2. A backed-out terminal. 3. A damaged terminal. 4. Poor terminal tension. 5. A chafed wire. 6. A broken wire inside the insulation.
Inspect OEM wiring harness routing. Look for possible contact points where chafing could occur leading to an open circuit condition. Moving parts on the vehicle could be contacting the harness, such as the parking brake drum, or suspension components.
When diagnosing for an intermittent short or open circuit condition, massage the wiring harness while watching the test equipment for a change.
CIRCUIT DESCRIPTION: The TCM monitors the status of the pressure switches at start-up to detect the presence of hydraulic pressure.
ACTION TAKEN WHEN THE DTC SETS: 1. The CHECK TRANS light is not illuminated (non-OBD II strategy). 2. The TCM forces Variable Modulated Main off. 3. A latched range inhibit is commanded. Operator is required to reselect range. 4. DTC is stored in the TCM history.
CONDITIONS FOR CLEARING THE DTC: The diagnostic tool may be used to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: 1. DTC P0701 may be logged if a forward or reverse range is selected immediately after the engine is started and before the TCM detects pressure at the switches. 2. A plugged control main filter may cause this DTC to set. 3. A cracked internal suction filter tube or damaged tube seal may cause this DTC to set. 4. A stuck lube regulator valve (located in the front support) may cause this DTC to set. A high static oil level with the vehicle running is often a good indication of this complaint. Often pressure switch DTCs are set in this scenario. 5. You may have to drive the vehicle in order to experience a fault. 6. Use of a shallow sump filter in a deep sump pan can also set this DTC. Inspect for correct filter size.
CIRCUIT DESCRIPTION: Service brake status is relayed to the TCM by a mechanical switch, or over the J1939 datalink indicating the service brake has been applied. Input wire 162 is used to send a positive signal to the TCM. DTC P0703 is only triggered when input wire 162 is being used for the brake switch and when the number of vehicle accelerations with brake switch “ON” exceeds a calibration value or when the number of vehicle decelerations to a stop with the brake switch “OFF” exceeds a calibration value. This code will not be triggered if the Service Brake Status Input is broadcast on J1939 datalink.
ACTION TAKEN WHEN THE DTC SETS: 1. The TCM forces Variable Modulated Main off. 2. The CHECK TRANS light is not illuminated. 3. No grade braking is allowed. 4. Use the default assumption that the brake is off. 5. Neutral at Stop is disabled (if equipped).
CONDITIONS FOR CLEARING THE DTC: The diagnostic tool may be used to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: The following procedures are not documented in any OEM procedures or in any OEM Troubleshooting or Service information and should not be used as a method to diagnose any transmission DTCs, function, or shift quality concern:
1. Back-probing any connections used for transmission features or functions may damage and/or unlock terminals from the back-probed connector creating permanent or intermittent shorts and/or open circuits. If possible, use the J-39700 Breakout Box, the appropriate harness adapters, and appropriate magnetic overlays to troubleshoot the vehicle.
2. Load-testing any transmission-related circuits with any other electrical devices such as vehicle lamps or relays, especially with the TCM connected to the harness. Use J-39700 Breakout Box and appropriate harnesses with the diagnostic tool to monitor the circuit performance in question unless otherwise specified in the various Troubleshooting information.
3. Piercing a wire to check for voltages, shorts-to-grounds or other wires anywhere in the circuit but especially at the TCM. This creates a leak path for moisture and damages the wire and insulation.
4. DTC P0703 indicates the TCM did not see the proper positive input signal for service brake status during an acceleration or deceleration cycle. This may indicate an open or short at the brake switch.
Inspect the wiring for poor electrical connections at the TCM. Look for the following conditions: 1. A bent terminal. 2. A backed-out terminal. 3. A damaged terminal. 4. Poor terminal tension. 5. A chafed wire. 6. A broken wire inside the insulation.
Service brake status can be on either a hardwired brake switch or on the datalink. Use the diagnostic tool to determine how the brake status is communicated.
When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
You may have to drive the vehicle in order to experience a fault.
Currently, this DTC is specific to vehicle applications that use grade braking feature only.
CIRCUIT DESCRIPTION: An Internal Mode Switch (IMS) is used by the TCM to detect the angular position of the shift selector shaft. There are five internal switches in the IMS: A, B, C, P, and NS. The TCM uses four of these switch inputs to determine the proper gear range that is selected. The fifth switch (NS), located in the IMS, is used as confirmation that the transmission is in neutral before the engine starter is engaged. DTC P0706 sets when the Engine Control Module (ECM) allows a start in reverse or forward range.
ACTION TAKEN WHEN THE DTC SETS: 1. The CHECK TRANS light illuminates (non-OBD II strategy). 2. The diagnostic response is to shut all solenoids off, allowing the transmission to fail to hydraulic default “limp home”. Shift selector and hydraulic state of logic valves determines range. 3. DTC P0706 is stored in the TCM history. 4. The TCM inhibits Torque Converter Clutch (TCC) engagement. 5. Due to this failure and associated response, DTC P0722 can also set. 6. A shift to R (Reverse) will allow reverse range if DTC P0878 is not active. 7. The TCM forces Variable Modulated Main off.
CONDITIONS FOR CLEARING THE DTC: Use the diagnostic tool to clear the DTC from the TCM history. The TCM automatically clears the DTC from the TCM history if the vehicle completes 40 warm-up cycles without the DTC recurring.
DIAGNOSTIC AIDS: The following procedures are not documented in any OEM procedures or in any OEM Troubleshooting or Service information and should not be used as a method to diagnose any transmission DTCs, function, or shift quality concern:
1. Back-probing any connections used for transmission features or functions may damage and/or unlock terminals from the back-probed connector creating permanent or intermittent shorts and/or open circuits. If possible, use the J-39700 Breakout Box, the appropriate harness adapters, and appropriate magnetic overlays to troubleshoot the vehicle.
2. Load-testing any transmission-related circuits with any other electrical devices such as vehicle lamps or relays, especially with the TCM connected to the harness. Use J-39700 Breakout Box and appropriate harnesses with the diagnostic tool to monitor the circuit performance in question unless otherwise specified in the various Troubleshooting information.
3. Piercing a wire to check for voltages, shorts-to-grounds or other wires anywhere in the circuit but especially at the TCM. This creates a leak path for moisture and damages the wire and insulation.
Inspect the wiring for poor electrical connections at the TCM. Look for the following conditions: 1. A bent terminal. 2. A backed-out terminal. 3. A damaged terminal. 4. Poor terminal tension. 5. A chafed wire. 6. A broken wire inside the insulation.
When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
You may have to drive the vehicle in order to experience a fault.
