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P1621 GMC Code - Control Module Long Term Memory Performance Condition

- Code Popularity: 10,038 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC P1621 GMC?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Powertrain Control Modules (PCM)
  • Low car battery voltage
⚠ Does your GMC have Safety Recalls? → Check here

How to Fix the DTC P1621 GMC?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1621 GMC code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

When is the Code Detected?

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 will set.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P1621 GMC 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.

OBDII Code P1621 GMC - Control Module Long Term Memory Performance Condition - AutoCodes.com
P1621 GMC Code - Control Module Long Term Memory Performance Condition

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Code P1621 GMC comments

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