GUIDE ASSEM. 8M6689 - Caterpillar

Use this procedure to troubleshoot the electrical system if a problem is suspected with a Temperature Control Module (TCM). Also, use this procedure if one of the diagnostic codes in Table 1 is active.
Table 1
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:
Illustration 1 g01640454
Components of the electronic fluid temperature control for the cooling system
(1) TCM
(2) Variable position electric motor
(3)