Applicable Systems
OBD-II
Symptoms
ECM keep-alive memory (KAM) error; adaptive fuel trim values lost; ECM must relearn from baseline.
Possible Causes
- Battery disconnect caused KAM loss
- ECM internal memory fault
- Battery low causing memory corruption
Troubleshooting Steps
- Step 1: Check battery condition and connections
Battery healthy, connections clean - Step 2: Clear code and perform drive cycle for relearn
Code does not return after drive cycle - Step 3: If code returns, ECM internal memory fault
ECM memory verified - Step 4: Replace ECM if KAM error persists after battery check
New ECM holds KAM - Step 5: Program new ECM and verify
All adaptive values learned
How to Reset
Clear with OBD-II scanner; requires drive cycle for relearn.
Frequently Asked Questions
- Q: What is KAM?
Keep-Alive Memory - ECM memory retained when key is OFF. Stores adaptive fuel trims, idle learned values, and transmission adaptive pressures. Battery disconnect erases KAM.
Source: SAE J2012 standard DTC list + OBD-II portal
Category: OBD-II