P0616 Starter relay: signal or voltage too low

By: Diagno editorial team · Updated: 2026-10-15

P0616 means: Starter relay: signal or voltage too low. The computer controls the starter or monitors its signal. Drive gently and have the car checked soon. The repair usually costs about €40–250 in Estonia. The most common cause: connector loose, damp or corroded. Other possible causes: wire broken or shorted to ground, faulty starter or relay.

What it means

The computer controls the starter or monitors its signal. There is a fault in the starter circuit or its control. The signal voltage is too low. Usually a wire is broken, a connector is loose or a wire is shorted to ground.

What you may notice

• The engine won't start or the starter won't turn
• The starter keeps running
• Engine light may be on

What could be wrong

1. 1Connector loose, damp or corroded
2. 2Wire broken or shorted to ground
3. 3Faulty starter or relay
4. 4Engine computer fault (rare)

Repair difficulty: Moderate

What you can check yourself

First look at the connector and wiring: anything loose, melted or green with corrosion? Check the battery. A car with an automatic gearbox only starts in P or N. You can check the simple things yourself, but the repair is best done in a workshop.

How we fix it

1. We read the fault data on the diagnostic tool and check whether the fault is constant
2. We measure the circuit's supply, ground and signal
3. We repair the wire or replace the connector
4. If the wiring is fine, we replace the starter or relay

Standard SAE description: Starter Relay Circuit Low