Powertrain, generic (extended)

P2A2A Alternative Fuel Tank Shutoff Valve D Control Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2A2A marks an interrupted control circuit at shutoff valve D, which only exists on installations with four or more gas cylinders, mostly commercial trucks, vans and buses. When the module energizes the coil and measures no current, it stores this code. No manufacturer documents P2A2A publicly. If valves A to D all report open circuits at once, a shared feed is the suspect: in Ford's 2003 bi-fuel CNG design the tank solenoid draws its power through the inertia switch and the ALT fuel relay, and a multi-tank system wired that way would lose every valve together. A single code instead points to the coil, plug or lead of valve D. CARB's comprehensive component monitoring forms the legal basis.

Likely causes

Break in the branch of the harness leading to valve D
Coil of valve D open
Common supply via relay or inertia switch interrupted (several valve codes at once)

Symptoms

  • Check engine light
  • Reduced usable gas quantity

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,200
Time0.5–3 h

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

Parts involved

alt fuel tank shutoff valve dwiring harnessafcm

Related codes

P2A2BP2A2CP2A2DP2A26P2A2E

References: law.cornell.edu, static.nhtsa.gov, static.nhtsa.gov.