P2E82: Cold Start Engine Coolant Pump Overspeed

What it means

During cold start, the engine coolant pump exceeds the calibrated maximum speed. Indicates load lost or supply voltage too high.

At a glance

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

How it works

The engine coolant pump circulates coolant, and its speed is monitored during cold start. This code sets when the pump runs above its calibrated maximum speed, which can happen if pump load is lost or its supply voltage is too high.

Common causes

Most likely first.

1. Pump impeller damaged
2. Supply voltage above nominal

Symptoms

• Check-engine light may be on
• Unusual engine temperature behavior
• Cooling-system warning may appear

How to diagnose it

1. Check freeze-frame data and live coolant temperature and pump-speed readings to confirm the overspeed occurs during cold start.
2. Look for cooling-system warnings, coolant leaks, unusual temperature swings, or evidence that coolant is not circulating normally.
3. Inspect the coolant pump connector and wiring for damage, loose pins, or signs of an abnormal power connection.
4. Measure pump supply voltage under the conditions that set the code and compare it with the manufacturer's specification.
5. If supply voltage is within specification, test pump operation and inspect for impeller damage or loss of pump load.

Common fixes

• Secure the pump connector and repair damaged wiring or terminals.
• Correct an overvoltage condition in the pump's supply circuit.
• Replace the coolant pump if testing confirms a damaged impeller or abnormal speed.
• Restore coolant level and remove trapped air using the vehicle's specified procedure after pump work.

Can I keep driving?

Avoid extended driving until the cause is identified because abnormal pump speed can disrupt coolant circulation and temperature control. Stop safely if the engine temperature rises or a cooling-system warning appears.