Conditions for Setting the DTC
WARNING: This page is about a different car, the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban 3500 HD, and 2018 Chevrolet Suburban. However, it is still accessible from the selected car via links, so may be relevant.
P0667
- The TCM detects a 20 - 50°C (36 - 90°F) or greater difference between the transmission fluid temperature and the TCM substrate temperature, which depends on the average of the transmission fluid temperature, TCM substrate temperature, and the TCM power up temperature.
- The TCM detects a 8 - 10°C (14 - 18°F) or greater difference between the TCM power up temperature and the TCM substrate temperature, which depends on the average of the transmission fluid temperature, the TCM substrate temperature, and the TCM power up temperature.
- The above conditions have to be met for 5 min.
P0668
The TCM internal temperature is -249°C (-416°F) or less for 1 min.
P0669
The TCM internal temperature is 249°C (480°F) or greater for 1 min.