Powertrain, generic (extended)

P2508 ECM/PCM Power Input Signal High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2508 is set when a supply input of the engine module reads above its permitted range. Ford documents it for the 2023 6.7 L Power Stroke diesel: the module checks its internal 5 V supply rail and flags P2508 once that rail exceeds 5.5 V, with continuous monitoring, roughly 5 s to mature, and the module awake (key on, running or after-run). The same group also blocks the reductant quality sensor test while P2507 or P2508 is present. On the 2014 BOSS 302S module Ford gives P2508 an M in the indicator column. A raised internal rail suggests a regulator fault inside the module or an external short to a higher voltage. P0563 reports excessive system voltage instead, P06A6 a sensor reference out of range. P2507 is the low partner.

Likely causes

Internal 5 V regulator of the engine module defective
Supply or sensor wire shorted to battery voltage
Overvoltage from charging fault or jump start

Symptoms

  • Check engine lamp
  • Other diagnostics such as the DEF quality test suspended
  • Erratic sensor values possible

Repair estimate

DifficultyHardWorkshop job
Parts and labour€50–1,500
Time0.5–4 h

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

Parts involved

ecmvoltage regulatorpower distribution

Related codes

P2505P2507P0563P06A6

References: fordservicecontent.com, performanceparts.ford.com, law.cornell.edu.