Circuit Description

1998 Buick Regal 25th Anniversary EditionSECTION Circuit Description

Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. DTC P1651 set indicates an improper voltage level has been detected on the output circuit which controls the low speed cooling fans relay.

Conditions required to set DTC are:

  • Ignition is on.
  • An improper voltage level has been detected on fan 1 relay driver circuit.
  • Condition present for at least 30 seconds.
RENDER: 1.0x

NO RELATED

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