Cummins Blog

Cummins ISB CM550 (1990-94) Fault Code: 135 PID: 100 SPN: 100 FMI: 3 Oil Pressure Sensor Circuit

Posted by fadi mourad on

Circuit DescriptionThe oil pressure sensor is used by the electronic control module (ECM) to monitor the lubricating oilpressure. The ECM monitors the voltage on the signal pin and converts this to a pressure value. Theoil pressure value is used by the ECM for the engine protection system. Component LocationThe oil pressure sensor is located on the engine block, below and to the right of the ECM. Shop Talk1) If Fault Code 143 or 415 is not present, the problem is not related to the engine lubricationsystem.2) Your diagnostic tool can be used to monitor the oil pressure signal voltage going...

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Cummins ISB CM550 (1990-94) Fault Code: 134 PID: 29 SPN: 29 FMI: 4 Remote Throttle Position Sensor

Posted by fadi mourad on

Circuit DescriptionThe remote throttle pedal provides the driver’s throttle command to the electronic controlmodule (ECM) through the original equipment manufacturer’s (OEM) harness and the OEMinterface harness. The ECM uses this signal to determine the fueling command. Component LocationThe remote throttle pedal location varies with each OEM. Refer to the OEM manual. Shop TalkThe remote throttle position sensor is a potentiometer. The resistance specifications of thethrottle position sensor is as follows:1) Between supply and return = 2000 to 3000 ohms2) Between supply and signal: Released = 1500 to 3000 ohms; depressed = 200 to 1500 NOTE: If the remote throttle position...

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Cummins ISB CM550 (1990-94) Fault Code: 133 PID: 29 SPN: 29 FMI: 3 Remote Throttle Position Sensor

Posted by fadi mourad on

Circuit DescriptionThe remote throttle pedal provides the driver’s throttle command to the electronic controlmodule (ECM) through the OEM harness and the original equipment manufacturer’s (OEM)interface harness. The ECM uses this signal to determine the fueling command. Component LocationThe remote throttle pedal location varies with each OEM. Refer to the OEM manual. Shop TalkThe throttle position sensor is a potentiometer. The resistance specifications of the throttleposition sensor is as follows:1) Between supply and return = 2000 to 3000 ohms2) Between supply and signal: Released = 1500 to 3000 ohms; depressed = 200 to 1500 Note: If the throttle or throttle position...

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Cummins ISB CM550 (1990-94) Fault Code: 132 PID: 91 SPN: 91 FMI: 4 Accelerator Position Sensor CIrcuit

Posted by fadi mourad on

Circuit DescriptionThe accelerator position sensor is attached to the accelerator pedal. The accelerator positionsensor sends a signal to the electronic control module (ECM) when the driver pushes on theaccelerator pedal. The accelerator position circuit contains three wires: a +5-VDC SUPPLYwire (pin 29), a RETURN ground (pin 19), and a SIGNAL wire (pin 30). NOTE: The connector pin letters shown for the accelerator pedal wiring in thesetroubleshooting steps are examples of representative sensors. The connector pin assignmentscan vary with equipment manufacturer, but the base troubleshooting logic will still apply. Component LocationThe accelerator position sensor is located on the accelerator pedal. Shop...

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Cummins ISB CM550 (1990-94) Fault Code: 132 PID: 91 SPN: 91 FMI: 3 Accelerator Position Sensor Circuit

Posted by fadi mourad on

Circuit DescriptionThe accelerator position sensor is attached to the accelerator pedal. The accelerator positionsensor sends a signal to the electronic control module (ECM) when the driver pushes on theaccelerator pedal. The accelerator position circuit contains three wires: a +5-VDC SUPPLYwire (pin 29), a RETURN ground (pin 19), and a SIGNAL wire (pin 30). NOTE: The connector pin letters shown for the accelerator pedal wiring in thesetroubleshooting steps are examples of representative sensors. The connector pin assignmentscan vary with equipment manufacturer, but the base troubleshooting logic will still apply. Component LocationThe accelerator position sensor is located on the accelerator pedal. Shop...

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