P26F1: Starter Relay A Stuck Off

What it means

The control module monitors whether starter relay A switches on when commanded. It sets this code when the relay does not provide the expected switched output.

At a glance

• Usually lights the check-engine light

How it works

Starter relay A is expected to close when the module requests a start. P26F1 sets when the module does not detect the expected switched output, which can prevent cranking or make stop-start unavailable.

Common causes

Most likely first.

1. Starter relay contacts fail to close
2. Relay control circuit fault

Symptoms

• Engine may crank slowly or fail to start
• A starter or powertrain warning light may appear
• Stop-start function may be unavailable

How to diagnose it

1. Review freeze-frame data and scan-tool start commands to establish whether relay A was commanded on when the fault occurred.
2. Check battery condition and inspect relay A's fuse, socket, and terminals for low supply, corrosion, looseness, or heat damage.
3. Listen for cranking and check whether relay A's output changes when commanded, using scan data or the manufacturer's test procedure.
4. Test relay A contacts and the relay control wire for continuity and correct command, following the manufacturer's procedure.
5. If relay and wiring pass, check the starter circuit and module output for an open or other fault.

Common fixes

• Clean and secure relay A socket terminals and its power connection.
• Replace a failed relay A if it does not close when commanded.
• Repair an open or damaged relay A control wire.
• Repair a confirmed fault in the starter circuit or module output.

Can I keep driving?

If the engine will not crank or cranks slowly, avoid repeated start attempts because they can drain the battery; the vehicle may also lose stop-start operation. If it starts and runs normally, drive only as needed, since the fault could leave you unable to restart after stopping.