P0800 Fault Code

Transmission Control System (MIL Request)

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0800 fault code refers to a Transmission Control System (MIL Request) issue. This code indicates that the engine control module (ECM) has detected a malfunction in the transmission control system. The Transmission Control Module (TCM) plays a critical role in managing the transmission’s performance and operations. When this code is triggered, it means that the TCM has requested that the Malfunction Indicator Light (MIL) be activated due to a fault that has been detected in the system.

What are the symptoms of the P0800 code?

• Illumination of the check engine light
• Irregular transmission behavior
• Difficulty shifting gears or delayed shifts
• Unusual noises from the transmission
• Poor acceleration or performance issues

What causes the P0800 code?

• Faulty TCM
• Malfunctioning engine control module (ECM)
• Wiring issues or connectors related to the TCM
• Problems with the transmission solenoids
• Low transmission fluid levels or quality
• Internal transmission issues

How to fix P0800?

• Perform a complete diagnostic to confirm P0800 code
• Inspect and repair any wiring or connector issues related to the TCM
• Check and replace transmission fluid if necessary
• Replace or reprogram the TCM if faulty
• Ensure that all related components like solenoids are functioning correctly