Chrysler 63 Controller EEPROM Write Denied
How to read it
Code 63 reads as 6 flashes, pause, 3 flashes on the check-engine light. Cycle the ignition key on, off, on, off, then leave it on with the engine off, and count the flashes on the power loss or check-engine light.
New to flash codes? The How to Read Chrysler OBD-I Codes with the Key Cycle walks through the test and what the numbers mean. The general OBD-I guide covers the rest.
What does Chrysler code 63 mean?
Controller EEPROM Write Denied
Common causes of 63
- Internal controller EEPROM or memory fault
- Supply voltage dropping during a memory write
- Poor controller grounds interrupting the write
- Failed controller after a voltage spike
How to fix 63
- Check controller powers and grounds including fusible links
- Confirm charging voltage is not spiking before condemning the controller
- Inspect the controller connectors for corrosion and backed out pins
- Retest after the supply voltage holds steady
- Replace the controller only if the code returns with power and grounds good
- Clear the code and retest
Sources and review
Review: qualified. Read the source limits below.
- Chrysler OBD-I trouble codes, model and year page
live reference page (troublecodes.net)
Supports: code identity and Chrysler meaning
Fetched directly from the linked model page. Single publisher, so the record is qualified, not verified. Causes and check order are curator-written from the circuit the code names.
- Chrysler OBD-I trouble codes, model and year page
live reference page (troublecodes.net)
Supports: code identity and Chrysler meaning
Fetched directly from the linked model page. Single publisher, so the record is qualified, not verified. Causes and check order are curator-written from the circuit the code names.
Last updated 2026-10-10.
Report a correction for 63. Include your vehicle, the issue and a source if you have one.