P0817Generic code

P0817 Code: Starter Disable Circuit

The P0817 code means there is an electrical fault in the control circuit of the starter disable. It can keep the engine from starting. In rare cases it might let the engine start in gear, so always check that it does not.

Severity
High
Can I keep driving?
Yes, but with caution
Estimated cost
$20 to $300
Difficulty
Medium
System
Transmission
Applies to
All OBD2 vehicles

Updated Reviewed by Renzo Chacca

On this page

What the P0817 code means

The transmission or engine computer allows the engine to start only in P or N (or with the clutch pedal pressed), using a circuit that controls the starter relay.

The computer watches the control circuit from its own driver transistor. The P0817 code points to an electrical fault in that control circuit. Before you replace the component, check the fuse, relay, connector and wiring, because they are the most common cause.

If the circuit fails, the engine may not start in any position. In rare cases it could start with a gear engaged, so always check that this does not happen.

Always start with the simplest items: fuse, relay and connector. Then check power, ground and signal with the component connected (using back-probes), and finally the continuity of each wire up to the computer. Only if all of that is good should you replace the component.

P0817 code symptoms

  • Check engine light or another warning light on.
  • The engine will not start.

Likely causes of the P0817 code

  1. Damaged connector, loose, broken or corroded.
  2. Blown or faulty fuse or relay.
  3. Wiring cut or shorted between the component and the computer.
  4. Failed component: the coil, the motor or its internal electronics.

How to diagnose the P0817 code step by step

  1. Command the component with the scan tool and see whether it responds.
  2. Check the fuse and relay. Measure voltage on both sides of the fuse, and swap the relay with an identical one.
  3. Measure the supply at the connector. Battery voltage with the key on or when it is commanded.
  4. Measure the component resistance and compare it with the manual, and check the insulation to ground too.
  5. Check the control wire for continuity up to the computer and for shorts.

How to fix the P0817 code

  • Repair the connector, the wiring or the power supply.
  • Replace the starter disable circuit if it does not respond with correct power and command.
  • Clear the codes and verify the repair.

Technical reference data

  • 12 V circuit to the starter relay.
  • These are approximate values: check the manufacturer data for your vehicle.

Brand-specific notes

This code is frequent on Ford and GM vehicles.

P0817 on Ford

Frequent on Ford vehicles, so check the fuse, the relay and the connector first.

P0817 on GM

Frequent on GM vehicles, where the same simple checks come before replacing any part.

Frequently asked questions about P0817

What does the P0817 code mean?
It is a generic OBD2 code that means there is an electrical fault in the control circuit of the starter disable. That circuit controls the starter relay.
Can I drive with a P0817 code?
Yes, with caution, if the engine starts. The risk is that the engine might not start at all, or in rare cases might start in gear, so make sure the shifter is in P or N when you start it.
What does the starter disable circuit do?
The transmission or engine computer allows the engine to start only in P or N (or with the clutch pedal pressed), using a circuit that controls the starter relay.
Does the part always have to be replaced?
No. Check the fuses, relays, connectors and wiring first.
How much does it cost to fix P0817?
As a rough guide, between $20 and $300.
Will a P0817 code clear itself?
It can go out if the fault was a momentary bad connection, but a blown fuse or a failed relay will bring the P0817 code back.
What is the most common cause of P0817?
A damaged connector, a blown fuse or relay, or cut or shorted wiring. These are far more common than a failed component.

Related codes

Questions about the P0817 code

There are no questions about this code yet. Tell us about your case: vehicle, symptoms and what you have already checked.