5L40E/5L50E Transmission Over Temperature Message Possible DTC P0218 - Keywords automatic cool fluid hot oil overheat M22 M82 IPC message DIC center panel display
| Subject: | 5L40E/5L50E Transmission Over Temperature Message Possible DTC P0218 |
| Models: | 2004-2005 Cadillac SRX |
| 2005 Cadillac STS |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
The 5L40E/5L50E automatic transmission used in the Cadillac SRX may exhibit a condition of the IPC message center displaying "Transmission Over Temp Idle Engine" and a possible DTC P0218. The "Transmission Over Temp Idle Engine" message will typically come on within a few miles of driving.
Recommendation/Instructions:
The Transmission Fluid Bypass Valve should be checked for being stuck in the closed position.
The following checks will help determine that the Transmission Fluid Bypass Valve is stuck in the closed position.
| • | Both transmission oil cooler lines will be the same temperature and cool or warm to the touch, while the transmission oil pan is hot to the touch. |
| • | Removing the return transmission oil cooler line (lower line) to check flow into a container will yield zero flow. (The Transmission Fluid Bypass Valve starts to open at 152° F (67° C) and should be fully open at 168° F (76° C) |
| • | The Transmission Fluid Bypass Valve can be inspected by removing it from the vehicle and looking at the oil cooler line end of the valve an looking for a black rubber sleeve. If the black rubber sleeve is missing the valve was not assembled properly. |
If it is determined that the Transmission Fluid Bypass Valve is stuck closed the valve should be replaced. Vehicles built after December 2004 and all future built vehicles do not use the Fluid Bypass Valve. There are transmission oil cooler lines available for these vehicles that are designed to eliminate this valve. Sometime in the future the Fluid Bypass Valve may not be available from GMSPO. Transmission oil cooler line replacement to the newer design would be necessary if this occurs.
Note: The Transmission Fluid Bypass Valve is not part of the transmission and will not come with the transmission.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
