P2622 Throttle Position Output Circuit High

P2622 means the throttle position output line sits too high, typically because it is shorted to a supply wire or the driver in the sending module cannot pull it down. The receiver would read a value resembling wide-open throttle even at idle, which can confuse shift scheduling or torque calculations. There is no public manufacturer documentation for this exact code. CARB's comprehensive component rules oblige makers to detect shorts on output circuits, and GM's short-to-power check on its crank output (impedance toward power of 0.5 ohm or less, sampled every 100 ms) shows how such a test is commonly built. Inspect for a wire rubbing against a battery or ignition feed and for back-feed through a connector. P2620 is the open line and P2621 the short to ground.

Likely causes

Symptoms

• Stored code in the engine module
• Receiver acts as if at full throttle (harsh or late shifts)

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, gsi.ext.gm.com.