P2A2B Alternative Fuel Tank Shutoff Valve D Control Circuit Performance/Stuck Off

P2A2B is the functional fault of valve D: the module has commanded it open, but the pressure picture suggests that cylinder D is not contributing gas. Bus builder New Flyer gives figures for the scale involved: its tanks hold between 1,375 and 24,800 kPa, while the regulated side should read 648 to 827 kPa once the engine runs. When a valve sticks shut, its cylinder stays full, and bulletin SMB-169 has the technician close the hand valves of that tank and its neighbours before venting it through the purge line. No car or truck maker publishes P2A2B. A failed coil whose circuit still tests intact can produce the same picture. The sister codes P2A2A, P2A2C and P2A2D deal with the wiring of this solenoid.

Likely causes

Symptoms

• Check engine light
• Tank D stays at full pressure
• Reduced range on gas

Repair estimate

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

Parts involved

Related codes

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