Pinpoint Test B: Transmission Fluid Heater Coolant Control Valve
- Refer to TRANSMISSION CONTROLS - 10R80
for schematic and connector information.
Normal Operation and Fault Conditions
The transmission fluid heater coolant control valve is an electrically controlled solenoid that allows or bypasses the flow of engine coolant through the transmission fluid cooler. This electrically controlled valve is normally open when not energized. The valve receives fused battery voltage when the ignition is in the run or start position and is grounded by the PCM via a low side driver. The PCM monitors the solenoid and circuits for electrical faults and sets an appropriate DTC.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P2681:00 Engine Coolant Bypass Valve "A" Control Circuit/Open: No Sub Type Information This DTC indicates an open circuit in the transmission fluid heater coolant control valve circuit. PCM P2682:00 Engine Coolant Bypass Valve "A" Control Circuit Low: No Sub Type Information This DTC indicates an open circuit or a short to ground in the transmission fluid heater coolant control valve circuit. PCM P2683:00 Engine Coolant Bypass Valve "A" Control Circuit High: No Sub Type Information This DTC indicates a short to power in the transmission fluid heater coolant control valve circuit. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- Circuit open or shorted
- BJB fuse
- Transmission fluid heater coolant control valve
- PCM
- B1 CHECK THE TRANSMISSION FLUID HEATER COOLANT CONTROL VALVE POWER CIRCUIT FOR VOLTAGE
- Disconnect Transmission fluid heater coolant control valve C1702.
- Inspect the connector for damaged or pushed out terminals.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C1702-1 Ground
Is the voltage greater than 11 volts?
Yes GO to B2 No CHECK BJB fuse F8 (20A). If the fuse is OK, REFER to the OEM WIRING DIAGRAMS to identify and repair an open circuit. If the fuse is not OK, REFER to the OEM WIRING DIAGRAMS to identify and repair a short to ground. - B2 CHECK THE TRANSMISSION FLUID HEATER COOLANT CONTROL VALVE CONTROL CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect PCM C175T.
- Inspect the connector for damaged or pushed out terminals.
Is the resistance less than 3 ohms?
Yes GO to B3 No REPAIR the open circuit. - B3 CHECK THE TRANSMISSION FLUID HEATER COOLANT CONTROL VALVE CONTROL CIRCUIT FOR A SHORT TO GROUND
- Measure:
Positive Lead Measurement / Action Negative Lead C1702-2 Ground
Is the resistance greater than 10, 000 ohms?
Yes INSTALL a new transmission fluid heater coolant control valve. REFER to: Transmission Fluid Heater Coolant Control Valve . No REPAIR the short to ground. - Measure: