Cumminz

Circuit DescriptionThe engine control module (ECM) receives a signal from the engine speed/position sensor. This signal is then sent to the fuel pump to indicate where top dead center is for each cylinder. Component LocationThe engine speed/position sensor is located on the fuel-pump side of the block, behind the starter. Shop TalkThe fuel pump controller monitors/processes 10- to 12-VDC square wave signals at pin 8 (engine harness pump end). The leading edge of this wave is the top dead center reference for the pump. The reference signal must occur within a defined window. If an engine pulse is not recognized...

Circuit DescriptionThis circuit is used for limp home acceleration if communication between the engine controlmodule (ECM) and fuel pump is lost. The circuit allows for a two-stage acceleration wherethere are only two engine speeds available throughout the full range of accelerator travel. Component LocationThis circuit is internal to the fuel pump control module and the engine ECM.

Circuit DescriptionThis circuit is used for limp home acceleration if communication between the engine controlmodule (ECM) and fuel pump is lost. The circuit allows for a two-stage acceleration wherethere are only two engine speeds available throughout the full range of accelerator travel. Component LocationThis circuit is internal to the fuel pump control module and the engine ECM.

Circuit DescriptionThis circuit provides a secondary fuel shutoff signal from the engine control module (ECM) to the fuel pump. Component LocationThe fuel pump is located on the back side of the gear housing. Shop TalkThe fuel pump controller disables fuel injection if a greater-than-6-VDC signal is registered at pin 5 (pump connector end) for 1 second. This signal line is triggered if an engine protection limit is exceeded or if a pump controller defect is set.Normal engine operation is as follows:1) 0-VDC at pin 5 at keyswitch ON2) 12-VDC at pin 5 at keyswitch OFF, until ECM powers down.Check for...

Circuit DescriptionThis circuit provides a secondary fuel shutoff signal from the engine control module (ECM) to the fuel pump. Component LocationThe fuel pump is located on the back side of the gear housing. Shop TalkThe fuel pump controller disables fuel injection if a greater-than-6-VDC signal is registered at pin 5 (pump connector end) for 1 second. This signal line is triggered if an engine protection limit is exceeded or if a pump controller defect is set.Normal engine operation is as follows:1) 0-VDC at pin 5 at keyswitch ON2) 12-VDC at pin 5 at keyswitch OFF, until ECM powers down.Check for...