Invalid Data from Ion Sense Module
What it means
A module received data from the ion sense module that failed its validity checks. The ion sense module reads current across the spark plugs to judge combustion and detect misfire. This is a data-quality fault, not a total loss of communication.
Can I keep driving? Usually yes short term, but a misfire can damage the catalyst, so get it read soon.
What this part usually does
The ion sense module monitors the tiny electrical current that flows through the flame in an engine cylinder during combustion, using the spark plug as a sensor. The engine control module uses this information to detect misfire, knock or other combustion quality issues without extra sensors. A fault may cause the engine to run less smoothly or turn on the check engine light.
Common symptoms
What you'll notice
- Check-engine light on
- Misfire or rough running
- Possible reduced power
- Poor economy
Common causes
Most likely first
- Wiring or connector fault between the ion sense module and the engine computer
- Poor power or ground at the ion sense module
- Electrical interference or a damaged ignition component near the module
- Faulty ion sense module
- Engine computer fault
How to diagnose & fix
Work through it in order
- Read codes from all modules and note any ignition or misfire codes.
- Check battery voltage and the ion sense module's power and ground.
- Inspect its connector and wiring for corrosion, looseness or damage.
- Check spark plugs and coil connections for faults that could corrupt the signal.
- Replace the module only if power, ground and wiring check out.
Related codes
Read & clear U0901 yourself
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