P0861

Gear Shift Control Module A Communication Circuit Low

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$56–278 (est.)

Symptoms

Incorrect gear shifting
Difficulties when shifting gears
Transmission transition to emergency mode
Check Engine light comes on
Power Loss

Causes

Open or short circuit in TCM communication circuit
Poor contact in TCM connectors
Shift control module malfunction
TCM power or ground problems
PCM (main control unit) malfunction

How to Fix

Check the integrity of wires and connectors in the TCM communication circuit
Check TCM supply voltage and ground
Scan the TCM for additional trouble codes
Replace the shift control module if necessary.
Check and update PCM software if necessary

Related codes

P0862 P0863 P0864