Honda Car Error Code P0128
Coolant Below Thermostat Temp
Severity
DIY Difficulty
Est. Cost
$20 - $200
Est. Time
45 min
What Does P0128 Mean?
Honda car error P0128 means coolant below thermostat temp. This is a moderate issue with a DIY difficulty of 3/5. Most repairs cost between $20 and $200.
Common Causes
Sensor malfunction
This is a common and usually minor cause of the P0128 error on Honda cars.
Minor blockage
This is a common and usually minor cause of the P0128 error on Honda cars.
Connection issue
This is a common and usually minor cause of the P0128 error on Honda cars.
Step-by-Step Fix
Power cycle the appliance
Unplug your Honda car for 60 seconds, then plug it back in. This clears temporary errors and resets the control board.
Check for obvious issues
Inspect your car for any visible problems such as loose connections, blockages, or unusual sounds. Many P0128 errors on Honda units are caused by simple issues.
Run a diagnostic cycle
Many Honda cars have a built-in diagnostic mode. Check your user manual for the specific key combination to enter diagnostics on your model.
Test related components
Based on the P0128 error meaning (Coolant Below Thermostat Temp), check the specific components involved. Use a multimeter to test for continuity if you are comfortable with electrical testing.
Contact a professional
If the above steps do not resolve the P0128 error, contact a certified Honda technician. This repair has a difficulty rating of 3/5 and may require specialized tools.
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