Common Symptoms
- Check engine light illuminated
- DEF system warning light on
- Reduced engine power or derate
- DEF consumption appears abnormal
- Vehicle may enter limp mode
Most Likely Root Causes
- Faulty DEF injector
- Shorted wiring or connector to DEF injector
- Damaged DEF injector control circuit
- Failed DEF dosing module or control unit
- Corrosion in DEF injector electrical connector
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Component Location
The DEF injector is located in the exhaust system upstream of the SCR catalyst, typically mounted on the decomposition tube or exhaust pipe.
Manufacturer Notes
Diesel exhaust fluid contamination or crystallization can cause injector electrical issues requiring injector and wiring inspection.
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