Powertrain, generic (extended)

P2552 Throttle/Fuel Inhibit A Circuit

Check engine lightUsually off
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2552 is the general circuit fault of throttle/fuel inhibit A, a line over which the engine module can be told, or can itself command, that throttle opening or fuelling must be blocked. It acts as a safety path next to the normal pedal-to-throttle chain. Ford lists P2552 in the engine module code table of its 2014 BOSS 302S race car, worded as circuit/open; its lamp column stays empty, and Ford gives no thresholds. A 2005 GM diagnostic summary for the L66 3.5-litre V6 shows how such a line is monitored, though only with the narrower codes P2553 to P2555, which test the inhibit relay and the voltage on the inhibit circuit after ignition off. If the path is broken, the module may limit power to stay safe. P2553 is the plausibility fault, P2554 and P2555 low and high.

Likely causes

Inhibit line open, e.g. broken wire or pushed-out pin
Inhibit relay or its supply defective
Engine module input or output stage faulty

Symptoms

  • Usually no check engine light (Ford non-MIL)
  • Possible power limitation or no throttle response

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–500
Time0.5–2.5 h

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

Parts involved

throttle inhibit awiring harness

Related codes

P2553P2554P2555P2108

References: performanceparts.ford.com, gsi.ext.gm.com.