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TuningBot DTC Database · v4.37.15

P0688 ECM/PCM Power Relay Sense Circuit/Open

Generic (OBD-II) interpretation in the TuningBot DTC database.

P · PowertrainBatteryOBD2

What P0688 means

P0688
ECM/PCM Power Relay Sense Circuit/Open Generic · battery Data confidence 90%

The control module detected an interruption (open circuit) in the ECM/PCM Power Relay Sense circuit, so the expected electrical continuity was not present.

Possible causes

  • Wiring short to positive
  • engine control relay
  • ECM

Related and nearby codes

How to read P0688

P

Powertrain: engine, transmission and driveline systems.

0

Generic SAE-standard code: same meaning on every make.

688

Specific fault index within the subsystem.

Frequently asked questions about P0688

What does P0688 mean?

ECM/PCM Power Relay Sense Circuit/Open. The control module detected an interruption (open circuit) in the ECM/PCM Power Relay Sense circuit, so the expected electrical continuity was not present.

Is P0688 generic or manufacturer-specific?

P0688 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove P0688 at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

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