Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.

A high resistance condition on the accelerator pedal position circuits could cause a DTC to set.
Ensure that the in-line harness connector seals are installed correctly. Improper installation could result in water intrusion into the connector and cause a DTC to set.
Vehicles equipped with a M5U-8L90 transmission utilize a 2 stage APP sensor that contains an electro-mechanical switch. Additional effort is required to depress the pedal to WOT in order overcome the additional spring tension at or near 100% throttle.