Common Symptoms
- Malfunction indicator lamp illuminated
- Reduced engine power or derate
- Poor fuel economy
- Failed emissions test
- Diesel exhaust fluid system warning message displayed
Most Likely Root Causes
- Failed DEF injector
- Open or damaged wiring harness to DEF injector
- Corroded or loose electrical connector at DEF injector
- Failed DEF dosing control module
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Component Location
The DEF injector for Bank 2 Unit 1 is mounted in the exhaust system upstream of the SCR catalyst on the second cylinder bank.
Manufacturer Notes
This code indicates an open circuit condition in the DEF injector control circuit for the second cylinder bank aftertreatment system.
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