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Electronic Control System Gas Plus Engines – FAULT CODE 115 – B and C Plus

Engine Position Sensor Circuit – Both Signals Lost

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Overview

CODE REASON EFFECT
Fault Code: 115
PID: P190
SPN: 190
FMI: 2
LAMP: Red
SRT: 

Engine position sensor circuit – both signals lost.

Engine can possibly die or will
not start.

Engine Position Sensor Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The engine position sensor is a magnetic sensor that provides engine speed and position to the electronic control module. This sensor generates a signal from the movement of target teeth machined into the rear side of the camshaft gear.

Component Location

The engine position sensor is located in the gear housing behind the air compressor.
Refer to Procedure 100-002 (Engine Diagrams) in Section E for a detailed component location.

Shop Talk

During normal engine operation, the intake manifold is under a vacuum (less than atmospheric pressure). When the intake manifold pressure indicates a vacuum, the engine will be running. Fault Code 115 can become active with the keyswitch on and the engine RPM at zero, if the intake manifold pressure indicates a pressure that is different than expected. INSITE™ electronic service tool can be used to compare the intake manifold pressure sensor to the mixer inlet pressure sensor. These two sensors
must both be equal and read atmospheric pressure (101.3 kPa [14.7 psia] at sea level) with the keyswitch on and the engine
not running. If these are
not equal, it possibly indicates an in-range failure of the intake manifold pressure sensor. The engine will possibly
not start if this condition exists.

Check the engine position sensor for engine oil contamination. Engine oil will wick through the wires into the connector. Also check the tip of the sensor for damage, the tip can extrude out of the sensor body and contact the camshaft gear, damaging the sensor.

Cautions and Warnings

 CAUTION 

To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM.
 CAUTION 

To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement:
Part Number 3822758 – male Deutsch™/AMP™/Metri-Pack™ test lead
Part Number 3823995 – male Weather Pack™ test lead
Part Number 3823996 – female Weather Pack™ test lead.

Troubleshooting Steps

STEPS SPECIFICATIONS
STEP 1. Check the fault codes.  
  STEP 1A. Read the fault codes. Fault Code 115 active?
STEP 2. Check the engine position sensor.  
  STEP 2A. Inspect the engine harness and engine position sensor connector pins. Dirty or damaged pins?
  STEP 2B. Check the resistance of the sensor. 1000 to 2000 ohms?
  STEP 2C. Check for a short circuit to ground. Greater than 100k ohms?
  STEP 2D. Inspect the sensor for damage. Damaged sensor?
  STEP 2E. Read the fault codes. Fault Code 115 active?
STEP 3. Check the engine harness.  
  STEP 3A. Inspect the engine harness and ECM connector pins. Dirty or damaged pins?
  STEP 3B. Check for an open circuit. Less than 10 ohms?
  STEP 3C. Check for a short circuit to ground. Greater than 100k ohms?
  STEP 3D. Check for a short circuit from pin to pin. Greater than 100k ohms?
STEP 4. Clear the fault codes.  
  STEP 4A. Disable the fault code. Fault Code 115 inactive?
  STEP 4B. Clear the inactive fault codes. All fault codes cleared?

Guided Step 1 – Check the fault codes.

Guided Step 1A – Read the fault codes.

Conditions

  • Turn keyswitch ON
  • Connect INSITE™ electronic service tool.

Action

Read the fault codes.

Use INSITE™ electronic service tool to read the fault codes.

Fault Code 115 active?
YES NO
No Repair No Repair

Guided Step 2 – Check the engine position sensor.

Guided Step 2A – Inspect the engine harness and engine position sensor connector pins.

Conditions

  • Turn keyswitch OFF
  • Disconnect engine harness from the engine position sensor.

Action

Inspect the engine harness and engine position sensor connector pins for the following:

  • Loose connector
  • Corroded pins
  • Bent or broken pins
  • Pushed back or expanded pins
  • Moisture in or on the connector
  • Missing or damaged connector seals
  • Dirt or debris in or on the connector pins
  • Connector shell broken
  • Wire insulation damage
  • Damaged connector locking tab.

For general inspection techniques, refer to Procedure 019-361 (Components Connector and Pin Inspection) in Section 19.

Dirty or damaged pins?
YES NO

Repair the damaged pins. Repair or replace the engine harness, or replace the sensor, whichever has the damaged pins.

 No Repair

Guided Step 2B – Check the resistance of the sensor.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor.

Action

Check the resistance of the sensor.

  • Measure the resistance from the engine position sensor SIGNAL pin to the engine position sensor RETURN pin in the engine position sensor connector.
  • Measure the resistance from the engine position backup SIGNAL pin to the engine position backup RETURN pin in the engine position sensor connector.

Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Procedure 019-360 (Resistance Measurements Using a Multimeter) in Section 19.

SMALL | MEDIUM | LARGE

1000 to 2000 ohms?
YES NO
No Repair

Replace the sensor.
Refer to Procedure 019-038 (Engine Position Sensor (EPS)) in Section 19.

Guided Step 2C – Check for a short circuit to ground.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor
  • Engine position sensor is installed.

Action

Check for a short circuit to ground.

  • Measure the resistance from the SIGNAL pin in the engine position sensor connector, sensor side, to the engine block ground.
  • Measure the resistance from the backup SIGNAL pin in the engine position sensor connector, sensor side, to the engine block ground.

Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Procedure 019-360 (Resistance Measurements Using a Multimeter) in Section 19.

SMALL | MEDIUM | LARGE

Greater than 100k ohms?
YES NO
No Repair

Replace the sensor.
Refer to Procedure 019-038 (Engine Position Sensor (EPS)) in Section 19.

Guided Step 2D – Inspect the sensor for damage.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor
  • Remove the engine position sensor from the gear housing.

Action

Inspect the engine position sensor for the following:

  • Metal debris on the end of the sensor
  • Damage to the end of sensor, caused by the engine gear
  • Oil leakage or insulation problems, such as swelling
  • Damaged electrical potting in the sensing end of sensor.

Damaged sensor?
YES NO

Replace the sensor.
Refer to Procedure 019-038 (Engine Position Sensor (EPS)) in Section 19.

No Repair

Guided Step 2E – Read the fault codes.

Conditions

  • Connect all components
  • Turn keyswitch ON
  • Connect INSITE™ electronic service tool.

Action

Read the fault codes.

  • Start the engine and let it idle for 1 minute.
  • Use INSITE™ electronic service tool to read the fault codes.

Fault Code 115 active?
YES NO
No Repair No Repair

Guided Step 3 – Check the engine harness.

Guided Step 3A – Inspect the engine harness and ECM connector pins.

Conditions

  • Turn keyswitch OFF.
  • Disconnect engine harness connector 1 from the ECM.

Action

Inspect the engine harness and ECM connector pins for the following:

  • Loose connector
  • Corroded pins
  • Bent or broken pins
  • Pushed back or expanded pins
  • Moisture in or on the connector
  • Missing or damaged connector seals
  • Dirt or debris in or on the connector pins
  • Connector shell broken
  • Wire insulation damage
  • Damaged connector locking tab.

For general inspection techniques, refer to Procedure 019-361 (Components Connector and Pin Inspection) in Section 19.

Dirty or damaged pins?
YES NO

Repair the damaged pins. Replace the engine harness, or replace the ECM, whichever has the damaged pins.

 No Repair

Guided Step 3B – Check for an open circuit.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor
  • Disconnect engine harness connector 1 from the ECM.

Action

Check for an open circuit.

  • Measure the resistance from the engine position sensor SUPPLY pin in the engine harness sensor connector to the engine position sensor SUPPLY pin in the engine harness ECM connector.
  • Measure the resistance from the engine position sensor backup SUPPLY pin in the engine harness sensor connector to the engine position sensor backup SUPPLY pin in the engine harness ECM connector.
  • Measure the resistance from the engine position sensor RETURN pin in the engine harness sensor connector to the engine position sensor RETURN pin in the engine harness ECM connector.
  • Measure the resistance from the engine position sensor backup RETURN pin in the engine harness sensor connector to the engine position sensor backup RETURN pin in the engine harness ECM connector.
  • Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Procedure 019-360 (Resistance Measurements Using a Multimeter) in Section 19.

SMALL | MEDIUM | LARGE

Less than 10 ohms?
YES NO
No Repair

Repair the engine harness.

Guided Step 3C – Check for a short circuit to ground.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor
  • Disconnect engine harness connector 1 from the ECM.

Action

Check for a short circuit to ground.

  • Measure the resistance from the engine position sensor SUPPLY pin in the engine harness ECM connector to engine block ground.
  • Measure the resistance from the engine position sensor backup SUPPLY pin in the engine harness ECM connector to engine block ground.
  • Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Procedure 019-360 (Resistance Measurements Using a Multimeter) in Section 19.

SMALL | MEDIUM | LARGE

Greater than 100k ohms?
YES NO
No Repair

Repair or replace the engine harness.

Guided Step 3D – Check for a short circuit from pin to pin.

Conditions

  • Turn keyswitch OFF
  • Disconnect the engine harness from the engine position sensor
  • Disconnect engine harness connector 1 and connector 2 from the ECM.

Action

Check for a short circuit from pin-to-pin.

  • Measure the resistance from the engine position sensor SUPPLY pin in the engine harness ECM connector 1 to all other pins in the connector.
  • Measure the resistance from the engine position sensor SUPPLY pin in engine harness ECM connector 1 to all pins in engine harness ECM connector 2.
  • Measure the resistance from the engine position sensor backup SUPPLY pin in the engine harness ECM connector 1 to all other pins in the connector.
  • Measure the resistance from the engine position sensor backup SUPPLY pin in engine harness ECM connector 1 to all pins in engine harness ECM connector 2.
  • Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Procedure 019-360 (Resistance Measurements Using a Multimeter) in Section 19.

SMALL | MEDIUM | LARGE

Greater than 100k ohms?
YES NO
No Repair

Repair or replace the engine harness.

Guided Step 4 – Clear the fault codes.

Guided Step 4A – Disable the fault code.

Conditions

  • Connect all components
  • Turn keyswitch ON
  • Connect INSITE™ electronic service tool.

Action

Disable the fault code.

  • Start the engine and let it idle for one minute.
  • Use INSITE™ electronic service tool to verify that Fault Code 115 is inactive.

Fault Code 115 inactive?
YES NO
No Repair

Return to the troubleshooting seps or contact a Cummins® Authorized Repair Location if all steps have been completed and checked again.

Guided Step 4B – Clear the inactive fault codes.

Conditions

  • Connect all components
  • Turn keyswitch ON
  • Connect INSITE™ electronic service tool.

Action

Clear the inactive fault codes.

  • Use INSITE™ electronic service tool to clear the inactive fault codes.

All fault codes cleared?
YES NO
No Repair

Troubleshoot any remaining active fault codes.
Repair complete
Appropriate troubleshooting charts
Last Modified:  03-Dec-2008
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