Powertrain, generic (extended)

P2511 ECM/PCM Power Relay Sense Circuit Intermittent

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2511 covers short dropouts on the line through which the engine module reads back the output of its main relay. The relay is commanded on, yet the sensed voltage briefly vanishes and returns, typical of a chattering contact, a cracked solder joint in the relay or a loose terminal in the fuse box. No manufacturer documents this code publicly with thresholds or a bulletin; even Ford's 2014 BOSS 302S list jumps from P2510 to P2512. CARB requires input circuits of the comprehensive components to be monitored, and GM's 2014 diesel tables show how the same sense signal is evaluated for P2510. Steady low or high readings are P0689 and P0690, a relay that does not follow commands is P2510. Possible effects: brief stalls or resets.

Likely causes

Worn or chattering main relay contact
Loose relay socket or fuse box terminal
Sense wire breaking intermittently

Symptoms

  • Engine may stall briefly or hesitate
  • Several modules logging voltage-related codes

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–400
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

main relaysense wire

Related codes

P2510P0689P0690

References: law.cornell.edu, gsi.ext.gm.com.