Powertrain, generic (extended)

P2506 ECM/PCM Power Input Signal Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2506 is the plausibility variant: the supply reaching the engine module is electrically present but its value or behaviour does not fit the operating state. No passenger-car maker publishes how it detects this. The closest coded use is Deutz, whose EMR engine controller assigns P2506 with failure type 18 to a critical overcurrent in the ECU power supply, a reading that only makes sense as a performance check, not as a plain open or short. Ford lists P2506 with an M in the indicator column of its 2014 BOSS 302S code table. CARB requires makers to check input signals for rationality as comprehensive components. Clear low or high values belong to P2507 and P2508, dropouts to P2509. In practice the code points to supply wiring, relay or module.

Likely causes

Resistance in supply fuse, relay contact or connector
Excessive current drawn through the module supply (Deutz)
Internal supply monitoring of the module faulty

Symptoms

  • Check engine lamp (Ford lists it as MIL code)
  • Sporadic stalling or restarts of the module possible

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€30–700
Time0.5–3 h

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

Parts involved

main relaypower distributionbattery cables

Related codes

P2505P2507P2508P2509

References: serdia.deutz.com, performanceparts.ford.com, law.cornell.edu.