P0617: starter relay high voltage during an on command

P0617 is the high-voltage starter relay control fault in the documented low-side driver system. Here the controller checks the circuit while the driver is on; an incompatible high voltage indicates the short-to-power condition described by the source.

Command state changes the conclusion

A high control-circuit voltage with the driver off is not equivalent evidence. The relevant observation is failure of the circuit to respond electrically to an on command. The published detection specification corresponds to no more than 0.5 ohm between the signal and controller power, while the actual voltage limits remain controller specific.

The monitor requires at least 6.41 volts of run/crank supply and accumulates forty failed samples out of fifty, at fifty milliseconds per sample. Therefore, a brief event and a full failed sampling window are different diagnostic outcomes.

Verify the control side

The code does not measure whether the motor cranks at the right speed and does not identify a failed motor winding. Record relay command, diagnostic status and the relevant voltage context before linking it to a no-crank complaint. Those observations help separate the driver detection from other parts of starting operation.

Use the vehicle-specific procedure to resolve the electrical condition and verify that the on-state monitor passes. A successful start alone does not prove that an intermittent control-circuit failure has disappeared. The examples list Type B over two trips and provide no authority for jumping starter terminals or bypassing start interlocks.

Source and applicability

Documented monitors in gm-2025-03a, gm-2025-04b, model year 2025. These are module/calibration examples; vehicle, engine and transmission applicability must be confirmed independently. GM 2025-03a, page 405. GM 2025-04b, page 620.