P1621 CHEVROLET - Control Module Long Term Memory Performance Condition
- Faulty Powertrain Control Modules (PCM)
- Low car battery voltage
When is the code detected?
- Engine Light ON (or Service Engine Soon Warning Light)
P1621 Chevrolet Description
The Powertrain Control Modules (PCM) Electronically Erasable Programmable Read Only Memory (EEPROM) contains data essential to running the engine and transmission. The PCM stores critical preprogrammed data within the EEPROM, this data remains even if the vehicles' battery is disconnected. At power up, the PCM checks the integrity of this data.