Chevrolet P1221: Fuel Pump Secondary System Circuit Low Input
Is your scanner showing Chevrolet P1221?
No worries. We'll show you what it means and how to deal with it.
Chevrolet P1221: Fuel Pump Secondary System Circuit Low Input
OVERVIEWWhat Does The Chevrolet P1221 Code Mean?
Key on or engine running; and the PCM detected the voltage at the Fuel Pump Signal circuit (BK14) was less than 2v for 1.5 seconds since the last ignition reference pulse was detected.
What Are The Potential Causes Of The Chevrolet P1221 Code?
- Fuel pump relay power circuit is open (test power at Fuse 9)
- Fuel pump relay control circuit is open or shorted to ground
- Fuel pump relay signal circuit is open
- Fuel pump relay is damaged or has failed
- PCM has failed
Recommended Parts
Below are some recommended auto parts to help you address the trouble code affecting your vehicle and get it running smoothly again:
Note: During the purchasing process, please check carefully whether the part you want to buy fits your car!
Check This Video For Reference
Reference Sources
- 2000 Chevrolet Camaro and Pontiac Firebird Service Manual – Volume 1, page 1090.
- GM, 2013, Service Bullettin – Prior To Any Circuit Testing.
