Applicable Systems
OBD-II
Symptoms
MAF sensor signal voltage below minimum expected; ECM sees less airflow than actual; may run rich.
Possible Causes
- MAF sensor signal wire short to ground
- MAF sensor internal open circuit
- MAF relay/fuse blown
Troubleshooting Steps
- Step 1: Check MAF sensor +12V supply at connector
+12V present at supply pin - Step 2: Check signal wire for short to ground
No short to ground - Step 3: Check MAF fuse and relay
Fuse intact, relay operational - Step 4: Replace MAF sensor if signal low
New sensor signal within range - Step 5: Clear code and verify MAF reading
MAF reading normal at idle
How to Reset
Clear with OBD-II scanner after repair.
Common Replacement Parts
- MAF Sensor (OEM spec)
- MAF Fuse 15A
Frequently Asked Questions
- Q: What is normal MAF voltage at idle?
Typically 1.0-1.5V at idle, rising to 4.0-4.5V at wide open throttle. Check vehicle-specific specs.
Source: SAE J2012 standard DTC list + OBD-II portal
Category: OBD-II