| Diagnostic Codes Table | ||
|---|---|---|
| CDL Code and Description | Conditions which Generate the Code | System Response |
| 168-3 Battery Potential / Power Input 1 : Voltage Above Normal | The supply voltage to the TCM has exceeded 33.5 V. This code is reported by the TCM over the CAN data link (MID No. 094). | The code is logged. |
| 168-4 Battery Potential / Power Input 1 : Voltage Below Normal | The supply voltage to the TCM has dropped below 16 V. This code is reported by the TCM over the CAN data link (MID No. 094). | The code is logged. |
| 2349-19 Engine Coolant Pump Outlet Temperature Sensor : Data Error | The temperature control module reported that there is a problem with the circuit that is for the coolant temperature sensor. The problem is communicated to the Electronic Control Module (ECM) via the CAN data link. | The code is logged. The temperature control module commands the valve to the full open position. |
| 2853-9 Engine Aftercooler Coolant Temperature Control Module : Abnormal Update Rate | The engine ECM did not receive the expected data link information from the controller for the aftercooler temperature control module. | The code is logged. The aftercooler temperature control module begins to regulate the coolant temperature to the default temperature. |
| 2854-9 Coolant Temperature Control Module : Abnormal Update Rate | The engine ECM did not receive the expected data link information from the controller for the temperature control module. | The code is logged. The temperature control module begins to regulate the coolant temperature to the default temperature. |
| 4193-2 Engine Coolant Pump Outlet Temperature : Erratic, Intermittent, or Incorrect | The TCM detects an intermittent problem in the circuit for the coolant temperature sensor. This code is reported by the TCM over the CAN data link (MID No. 094). | The code is logged. |
| 4193-3 Engine Coolant Pump Outlet Temperature : Voltage Above Normal | The TCM detects an open circuit or a short to +Battery in the harness for the coolant temperature sensor. The three-way valve is commanded to the fault position. This code may be generated if the coolant temperature is less than −25° C (−13° F). This code is reported by the TCM over the CAN data link (MID No. 094). |
The code is logged. The three-way valve is commanded to the fault position. |
| 4193-4 Engine Coolant Pump Outlet Temperature : Voltage Below Normal | The TCM detects a short to ground in the harness for the coolant temperature sensor. This code is reported by the TCM over the CAN data link (MID No. 094). | The code is logged. The three-way valve is commanded to the fault position. |
This engine is equipped with an electronic fluid temperature control system. The system is used to control the flow of coolant through the cooling system. There are two basic components of the system:
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| Illustration 1 | g01640454 |
Components of the electronic fluid temperature control for the cooling system (1) TCM (2) Variable position electric motor (3) Three-way valve | |
Temperature Control Module (TCM) - The TCM receives a coolant temperature signal from the coolant temperature sensor that is installed in the outlet of the coolant pump. The TCM processes this input signal and outputs a voltage that is used to control the position of the coolant valve.
Three-way Valve - The valve assembly consists of a fixed housing, a piston plate, and a variable position electric motor. The valve housing has inlet piping and outlet piping that attaches to the cooling system. The piston plate is internal to the valve and rides on a lead screw. The variable position electric motor drives the lead screw in order to adjust the piston within the housing. The electric motor receives a voltage signal from the TCM in order to turn the lead screw and adjust the coolant flow through the valve.
For this application, the electronic fluid temperature control operates in a stand-alone mode. The temperature control module regulates the engine temperature to a default temperature of 85° C (185° F). When the secondary ECM has control of the engine, the ATCM and the TCM will operate at the default temperature. The control module is preprogrammed to control the engine coolant temperature during engine operating conditions. The control module regulates the flow of coolant through the cooling system in order to regulate the temperature of the engine coolant.
The TCM communicates diagnostic codes to the service tool over the CAN data link. The TCM also communicates data that is related to the engine coolant temperature and fault conditions to the engine ECM via the CAN data link. If an electrical fault occurs in the circuit for the coolant temperature sensor, the temperature control module communicates the condition to the ECM. When an electrical fault is received by the ECM, a 2349-19 diagnostic code is activated.
Note: Use Cat ET to clear diagnostic codes. Keyswitch power to the engine must be cycled to complete clearing of the codes from the TCM.
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| Illustration 2 | g02616018 |
Schematic for the TCM | |
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| Illustration 3 | g02616424 |
Location of the components for the coolant temperature control module (4) Temperature control module (5) Low current power distribution panel (6) High current power distribution panel | |
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| Illustration 4 | g02616822 |
Locations of the components at the control box (front engine view) (7) Right side rail connector (8) Primary ECM connector (9) Primary keyswitch relay (10) Engine interface connector (11) Front harness connector (12) Primary power connector | |
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| Illustration 5 | g01241538 |
Terminal locations at the temperature sensor at the outlet of the coolant pump (Terminal 1) Sensor signal (Terminal 2) Return | |
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
1. Check for Active Diagnostic Codes A. Connect Cat ET to the service tool connector. B. Restore the electrical power to the ECM. C. Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes. Note. Wait at least 30 seconds in order for the diagnostic codes to become active. D. Determine if a diagnostic code has occurred several times. Note. A diagnostic code that is logged several times is an indication of an intermittent problem. Most intermittent problems are the result of a bad connection between a socket and pin in the connector. An intermittent problem may also be caused by a poor connection between a wire and terminal. E. Look for the following diagnostic codes that are active or logged: - 168-3 - 168-4 - 2349-19 - 2853-9 - 2854-9 - 4193-2 - 4193-3 - 4193-4 F. Remove the electrical power from the ECM. |
Codes |
Result: No diagnostic codes are active for the TCM. There may be an intermittent problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct procedures for inspecting electrical connectors.. Result: A 168-3 or 168-4 diagnostic code is active. The TCM has detected there is a problem with the supply voltage to the unit. Proceed to Test Step 2. Result: AA 2853-9 diagnostic code is active. The ECM detects a problem with data link communications for the Aftercooler Coolant TCM. Proceed to Test Step 2. Result: A 2854-9 diagnostic code is active. The ECM detects a problem with data link communications for the TCM. Proceed to Test Step 2. Result: The 2349-19 diagnostic code is active. The ECM is reporting that the TCM detects a problem in the circuit for the temperature sensor at the coolant pump. Proceed to Test Step 4. Result: The 4193 diagnostic code is active. The TCM detects a problem in the circuit for the temperature sensor at the coolant pump Proceed to Test Step 4. |
2. Check the Supply Voltage at the TCM A. Disconnect the harness connector at the TCM. B. Restore the electrical power to the ECM. Ensure that the emergency stop switch is in the RUN position. Do not start the engine. C. Use a multimeter to measure the supply voltage between terminal 1 (+Battery) and terminal 5 (−Battery) on the harness side of the connector. D. Remove the electrical power from the ECM. |
Supply voltage between 18 V and 32 V. |
Result: The supply voltage is between 18 V and 32 V. The supply voltage is correct at the temperature control module. Proceed to Test Step 3. Result: The supply voltage is not between 18 VC and 32 V. Check the condition of the 10 Amp fuse that is in the low current power distribution panel. If the fuse is not blown, there is a problem in one of the harnesses. The problem is between the low current power distribution panel and the TCM. Be sure to check the condition of the crossover harness that is in the control box. Ensure that the repair has eliminated the original problem. |
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
3. Check for Keyswitch Power at the TCM A. Ensure that the harness connector for the temperature control module has been disconnected. B. Restore the electrical power to the ECM. Ensure that the disconnect switch is in the ON position. Ensure that the emergency stop switch is in the RUN position. Do not start the engine. C. Use a multimeter to measure the keyswitch power between terminal 8 (keyswitch) at the harness connector for the TCM, and the chassis ground. D. Remove the electrical power from the ECM. Restore the wiring to the original configuration. |
The voltage at the keyswitch input is 24.0 ± 3.0 V. |
Result: The voltage at the keyswitch input is 24.0 ± 3.0 V. There may be a problem with the wiring for the CAN data link. Repair the CAN data link. Refer to Troubleshooting, "Data Link - Test" for information that is related to troubleshooting the circuit. Result: The voltage at the keyswitch input is not 24.0 ± 3.0 V. Repair the keyswitch power is not reaching the controller. There is a problem in the keyswitch circuit. Repair the circuit. Refer to Troubleshooting, "Electrical Power Supply - Test" for information that is related to troubleshooting the keyswitch circuit. |
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
4. Check the Resistance of the Wiring Harness for the Sensor Circuit A. Ensure that the battery disconnect switch is in the OFF position. B. Fabricate a jumper wire that is long enough to create a short circuit at the sensor connector. Crimp connector pins to each end of the jumper wire. C. Check for an open circuit in the harness wiring: 1. Disconnect the connector from the suspect sensor. 2. Use the jumper wire to create a short circuit on the harness side of the sensor connector. 3. Disconnect the engine harness connector at the temperature control module. 4. Use a multimeter to check for continuity between terminal 3 and terminal 10 of the harness connector at the temperature control module. 5. Remove the jumper wire from the sensor connector. Leave the sensor disconnected. The correct measurement shows continuity while the wires are jumpered. D. Check for a short circuit to another wire in the harness: 1. Disconnect the engine harness connector at the temperature control module. 2. Use a multimeter to check for continuity between terminal 3 and all of the other terminals in the harness connector. Note: The return circuit for the sensor will show continuity to the circuit for the −Battery. 3. Use a multimeter to check for continuity between terminal 10 and all of the other terminals in the harness connector. The correct measurement shows that the circuit does not have continuity to any other wires that are in the harness. 4. Restore all of the wiring to the original configuration. |
Wire harness |
Result: The sensor circuit is not open or shorted. Repair: Repair the circuit for the temperature sensor that is at the outlet of the coolant pump is OK. There is a problem with the temperature sensor. There may be a problem with the temperature control module. Perform the following procedure: Temporarily connect a new sensor to the harness, but do not install the new sensor in the engine. Verify that the original diagnostic code is no longer active. If the code is no longer active, permanently install the new sensor. Clear any logged diagnostic codes. If the original diagnostic code remains active, reconnect the old sensor. The problem is with the temperature control module. Replace the temperature control module. Verify that there are no active diagnostic codes. Verify that the repair has resolved the original problem. Result: The sensor harness has an open or short circuit. There is a problem in the wiring harness. Repair the wiring harness or replace the wiring harness. Verify that the original problem has been resolved. |