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TuningBot DTC Database · v4.37.15

P0686 ECM/PCM Power Relay Control Circuit Low

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

P · PowertrainBatteryOBD2

What P0686 means

P0686
ECM/PCM Power Relay Control Circuit Low Generic · battery Data confidence 90%

The control module detected that the signal in the ECM/PCM Power Relay Control circuit stayed below the expected operating range.

Possible causes

  • Wiring short to earth
  • ECM/PCM power relay
  • ECM

Related and nearby codes

How to read P0686

P

Powertrain: engine, transmission and driveline systems.

0

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

686

Specific fault index within the subsystem.

Frequently asked questions about P0686

What does P0686 mean?

ECM/PCM Power Relay Control Circuit Low. The control module detected that the signal in the ECM/PCM Power Relay Control circuit stayed below the expected operating range.

Is P0686 generic or manufacturer-specific?

P0686 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove P0686 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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