P08C2: Pressure Control Solenoid L Control Circuit High

What it means

Voltage on the pressure control solenoid L control line is above the expected window. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

The TCM controls pressure control solenoid L through a monitored control line. P08C2 sets when voltage on that line is above the expected range, which can result from a short to battery voltage, an open solenoid coil, or a connector fault.

Common causes

Most likely first.

1. Control wire shorted to B+
2. Open solenoid coil
3. Connector pins corroded - high contact resistance

Symptoms

• Check engine or transmission warning light on
• Harsh, delayed, or missing shifts
• Possible limp mode (locked in one gear)
• Slipping or shuddering during gear changes

How to diagnose it

1. Review freeze-frame data and live circuit readings to confirm solenoid L control voltage is high when the code sets.
2. Inspect the L control wire for damage or contact with a battery-voltage feed, especially near harness bends and connectors.
3. Check solenoid L connector pins for corrosion, poor fit, water intrusion, or a pushed-back terminal that could interrupt the circuit.
4. Test coil continuity and check the control line for a short to battery voltage using the wiring diagram and manufacturer’s procedure.
5. If the wiring and coil pass, test the TCM output and circuit voltage against the manufacturer’s specification.

Common fixes

• Repair wiring shorted to battery voltage in the solenoid L control circuit.
• Replace solenoid L if its coil is open.
• Restore corroded, loose, or damaged connector terminals and seals.
• Repair the TCM output only if testing confirms it is producing an out-of-range high voltage.

Can I keep driving?

Limit driving if the transmission shifts harshly, slips, misses shifts, or enters limp mode; the high control voltage can prevent proper pressure regulation and continued slipping may cause damage. Arrange prompt repair.