P0CF5: Control Pilot Circuit Low

What it means

The control pilot signal (SAE J1772 / IEC 61851 charging) reports a circuit low condition. EV charging handshake compromised.

At a glance

• Usually lights the check-engine light

How it works

The control pilot provides the signaling that lets an EV and its charging equipment establish a charging session. This code sets when the pilot circuit signal is too low, commonly because it is shorted to ground or the inlet connection is damaged, and the charging handshake cannot be trusted.

Common causes

Most likely first.

1. Control pilot signal circuit shorted to ground
2. Damaged or contaminated charge inlet or cable connection

Symptoms

• Charge status indicator shows fault
• Charging may not start or interrupts
• Slower-than-expected charge rate

How to diagnose it

1. Check scan-tool and charge-status data and note whether the low pilot fault occurs with one EVSE or with multiple units.
2. Unplug and reconnect the cable as instructed, then check that the connector is fully seated and latched.
3. Inspect the charge inlet and cable plug for dirt, moisture, bent contacts, or damage that could pull the pilot signal low.
4. With the equipment disconnected and the vehicle made safe, inspect accessible pilot wiring for a short to ground, chafing, or damaged terminals.
5. Test the pilot circuit and inlet components against the manufacturer's specification to confirm the source of the low signal.

Common fixes

• Clean and correctly reseat the inlet and cable connection.
• Repair a pilot wire shorted to ground or damaged harness section.
• Repair or replace a damaged charge inlet or cable connector.
• Replace a faulty pilot-circuit component if testing identifies it.

Can I keep driving?

The code generally prevents or interrupts charging rather than limiting normal driving, but verify the battery has enough range before travelling. Do not use a visibly damaged or contaminated charging connector, and stop charging if the fault recurs.