Cummins ISB CM550 (1990-94) Fault Code: 372 PID: 1283 SPN: 1077 FMI: 11 Idle Select High/Low

Circuit Description
This circuit is used for limp home acceleration if communication between the engine control
module (ECM) and fuel pump is lost. The circuit allows for a two-stage acceleration where
there are only two engine speeds available throughout the full range of accelerator travel.

Component Location
This circuit is internal to the fuel pump control module and the engine ECM.