Fault-Code Library · Exhaust temperature sensing
P0544: Exhaust-gas temperature sensor circuit, bank 1 sensor 1
The ECU sees an electrical fault in an exhaust-temperature sensor used to protect the turbo and emissions system.
Common symptoms
- •DPF regeneration inhibited
- •Reduced power
- •Emissions warning
- •Cooling fan activity
Likely causes
- •Failed EGT sensor
- •Heat-damaged wiring
- •Connector corrosion
- •Exhaust-system repair damage
First checks
- •Compare all EGT readings from cold
- •Inspect harness routing near the exhaust
- •Check resistance against manufacturer data
Important
Incorrect temperature data can make forced regeneration unsafe.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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