Gear Shift Module Communication Circuit High

What it means

P0862 is stored when the engine control module measures a voltage in the Gear Shift Module Communication circuit above the expected maximum, typically because the signal wire is shorted to battery voltage or the circuit is open and pulled up internally.

This entry is compiled automatically from the standard definition and typical diagnostic practice for this type of fault. A detailed, reviewed article is in preparation.

Symptoms

• Check engine or transmission warning light
• Harsh, delayed or missing shifts
• Transmission stuck in one gear (limp mode)
• Shuddering or slipping under load

Common causes

1. Damaged, chafed or corroded wiring in the Gear Shift Module Communication circuit
2. Corroded, loose or water-damaged connector terminals
3. Failed Gear Shift Module Communication component (sensor, solenoid or actuator)
4. Poor ground connection for the module or component
5. Faulty control module driver (rare, confirm all else first)

How to diagnose

1. Read freeze frame data and note when the code set (cold start, under load, after rain)
2. Inspect the Gear Shift Module Communication connector for bent pins, corrosion and water; wiggle the harness with the engine running and watch live data
3. Measure supply voltage and ground at the connector with the key on
4. Check the signal wire for shorts to ground or battery and for continuity to the control module
5. Test or substitute the Gear Shift Module Communication only after wiring and connectors are confirmed good
6. Clear the code and complete a drive cycle to confirm the repair

Related codes

Nearby codes in this group

• P0861Gear Shift Module Communication Circuit Low
• P0863TCM Communication Circuit
• P0860Gear Shift Module Communication Circuit
• P0864TCM Communication Circuit Range/Performance
• P0859Traction Control Input Signal High
• P0865TCM Communication Circuit Low
• P0858Traction Control Input Signal Low
• P0866TCM Communication Circuit High