P1621 Cadillac Control Module Long Term Memory Performance Condition
Possible causes
– Faulty Powertrain Control Modules (PCM)
– Low car battery voltage
– Low car battery voltage
What about the obd code?
If the checksum of the Electronically Erasable Programmable Read Only Memory (EEPROM) does not match a predetermined value by the Powertrain Control Modules (PCM), DTC P1621 Cadillac will set.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1621 Cadillac 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.
Cadillac Vehicle:Cadillac CTS Coupe, Cadillac CTS-V Coupe , Cadillac Eldorado , Cadillac Escalade EXT , Cadillac ATS , Cadillac CTS , Cadillac CTS Sedan , Cadillac CTS Sport Sedan , Cadillac CTS-V , Cadillac CTS-V Sedan , Cadillac Catera , Cadillac DTS , Cadillac DeVille , Cadillac STS-V , Cadillac STS , Cadillac Seville , Cadillac XTS , Cadillac XLR , Cadillac XLR Platinum , Cadillac Escalade , Cadillac SRX