P2A66 code meaning
Alternative Fuel Tank C Level Sensor Circuit Low
Powertrain system Generic code P2Axx codes Check engine light
What P2A66 means
P2A66 says the tank C level signal is below its lower electrical bound. With voltage-output senders that typically comes from a signal wire grounded somewhere along its route, a sender shorted inside, or a missing supply to a ratiometric Hall module such as those Rochester builds for LPG vessels, which needs a few volts to produce any output. The display consequence is an empty or missing tank C, so a driver may refuel early or think the gas supply is shorter than it is. No manufacturer documents P2A66, and since the gasoline code family covers only two senders, the nearest documented relative is the tank B case P2A61. Disconnecting the sender should move the reading; if it stays low, trace the short in the harness.
P2A66 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A66
- Check engine light
- Tank C displayed as empty
- Refuelling earlier than needed
Common causes of P2A66
- Most likelyTank C sender signal wire grounded
- PossibleNo supply voltage at a Hall-type sender
- PossibleTank C sender shorted internally
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel tank c level sensorWiring harnessAfcm
What each part of P2A66 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| A | Area: hybrid propulsion. |
| 66 | The exact fault in that area. |
What to do next
- Note P2A66 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2A66
What does P2A66 mean?
P2A66 means "Alternative Fuel Tank C Level Sensor Circuit Low". P2A66 says the tank C level signal is below its lower electrical bound. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A66?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2A66 fail an emissions test?
Yes, it can. P2A66 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2A66 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P2A66 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.