LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2018 >> Grand Cherokee Laredo, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 59 (8HP45/845RE Automatic Transmission (Service Information)) >> Valve, Coolant Control >> Operation

Valve, Coolant Control: Operation

WARNING: This page is about a different variant/trim than selected.

The purpose of the coolant control valve is to control coolant flow to the transmission heater. Coolant is first directed from the engine to the valve, which allows the coolant to flow to the transmission heater when the transmission fluid is below the desired operating temperature. By getting coolant to the transmission heater, it allows the transmission to get to ideal operating temperature quicker so the transmission is operating efficiently.

The coolant valve is controlled and monitored by the Powertrain Control Module (PCM). The coolant valve has dedicated Diagnostic Trouble Codes (DTCs) that can be stored by the PCM.

The Coolant Shut off valve incorporates the following components:

GC0173606Courtesy of CHRYSLER GROUP, LLC

When the coolant control valve solenoid (1) is in the de-energized state, the lifting rod/spring/cone/seal assembly (3) is spring loaded upward and maintains a defined clearance between cone seal and valve housing (4). This allows coolant to flow through the coolant control valve from the inlet port to the outlet port, and from the outlet port through the transmission heater.

GC0173568Courtesy of CHRYSLER GROUP, LLC

When the coolant control valve solenoid (1) is energized by the PCM, the lifting rod/spring/cone/seal assembly (3) is actuated downward, pressing the cone seal against the valve housing (4). This lifting rod position blocks the coolant path between the inlet and the outlet port, allowing no coolant flow to the transmission heater.