DTC U1129 Isuzu

High Speed Cooling Fan Circuit Malfunction

High Speed Cooling Fan Circuit Malfunction

Description

Engine started, engine runtime over 5 seconds, system voltage over 10.0v, and the PCM detected the Actual and Commanded state of the High speed fan circuit did not match during the CCM test.

Cause and Solution

Cooling fan relay control circuit is open or shorted to groundCooling fan relay control circuit is shorted to system power (B+)Cooling fan relay power circuit is open (check the F19 fuse)Cooling fan relay is damaged or has failedPCM has

Video Guide

Duration: PT3M59S | Uploaded: 2020-06-21

Diagnostic Info

  • DTC Code: U1129
  • Brand: Isuzu
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