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Electronic Control System Gas Plus Engines – FAULT CODE 459 – L Gas Plus

Ignition Timing Signal Circuit – Shorted Low

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Overview

CODE REASON EFFECT
Fault Code: 459
PID: S67
SPN: 726
FMI: 4
LAMP: Red
SRT: 

Ignition Timing Signal Circuit – Shorted Low. Low voltage detected at the ECM.

Engine will die or
not start.

Ignition Timing Signal Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The ignition control module (ICM) is a distributorless ignition module that provides a signal to the coils and delivers high voltage to the spark plugs. The electronic control module (ECM) controls the ICM by providing ignition timing information.

Component Location

The ICM is located next to the ECM on the side of the engine.

Shop Talk

The ICM can
not detect whether there is a misfire or a malfunctioning spark plug. For the ICM to operate correctly, all connectors
must be clean and tight. Cylinders 3 and 4 are especially critical to the proper operation of the ICM. A poor connection in either of these areas will cause the engine
not to start.

Cautions and Warnings

 WARNING 

EXTREMELY HIGH VOLTAGE. Do not touch any ignition wiring or component while the engine is operating unless an insulated tool is being used to prevent electrical shock and damage to the equipment.
 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.

Troubleshooting Steps

STEPS SPECIFICATIONS
STEP 1. Check the fault codes.  
  STEP 1A. Read the fault codes. Fault Code 459 active?
STEP 2. Check the ignition control module (ICM).  
  STEP 2A. Check the system voltage. Less than 12-VDC?
  STEP 2B. Check the ICM supply voltage. Less than 12-VDC?
  STEP 2C. Inspect the ICM and engine harness connector pins. Dirty or damaged pins?
  STEP 2D. Check the ICM supply voltage. Less than 12-VDC?
  STEP 2E. Check for a damaged ICM 15 ampere fuse. Less than 10 ohms?
  STEP 2F. Read the fault codes. Fault Code 459 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 3E. Check the ECM for active fault codes. Fault Code 459 inactive?
STEP 4. Clear the fault codes.  
  STEP 4A. Disable the fault code. Fault Code 459 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 the INSITE™ electronic service tool.

Action

Read the fault codes.

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

Fault Code 459 active?
YES NO
No Repair No Repair

Use the following procedure for troubleshooting an inactive or intermittent fault code.
Refer to Procedure 019-362 in Section 19.

Guided Step 2 – Check the ignition control module (ICM).

Guided Step 2A – Check the system voltage.

Conditions

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

Action

Check the system voltage.

  • Use INSITE™ electronic service tool to read the Battery Voltage parameter.

Less than 12-VDC?
YES NO

Recharge or replace the vehicle battery.
Refer to Procedure 013-007 in Section 13.

No Repair

Guided Step 2B – Check the ICM supply voltage.

Conditions

  • Turn keyswitch ON.
  • Disconnect engine harness from ICM connector.

Action

Check the Switched Battery (+) voltage.

  • Measure the voltage at pin A at the ICM connector.

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

Less than 12-VDC?
YES NO
No Repair No Repair

Guided Step 2C – Inspect the ICM and engine harness connector pins.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the engine harness from the ICM connector.

Action

Inspect the module, engine harness, and OEM 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.

Use the following procedure for general inspection techniques.
Refer to Procedure 019-361 in Section 19.

Dirty or damaged pins?
YES NO

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

 No Repair

Guided Step 2D – Check the ICM supply voltage.

Conditions

  • Turn keyswitch ON.
  • Disconnect the engine harness from the 31-pin OEM connector.

Action

Check the Switched Battery (+) voltage.

  • Measure the voltage at pins 27 and 30 at the OEM connector.

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

Less than 12-VDC?
YES NO
No Repair No Repair

Guided Step 2E – Check for a damaged ICM 15 ampere fuse.

Conditions

  • Turn keyswitch OFF.
  • Remove the 15 ampere ICM fuse.

Action

Check for a damaged fuse.

  • Remove the 15 ampere ICM fuse.
  • Use a multimeter to test the continuity of the fuse.

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

Use the following procedure for general resistance measurement techniques.
Refer to Procedure 019-360 in Section 19.

Less than 10 ohms?
YES NO
No Repair

A damaged fuse has been detected. Replace the fuse.

Guided Step 2F – 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 459 active?
YES NO
No Repair No Repair

Guided Step 3 – Check the engine harness.

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

Conditions

  • Turn keyswitch OFF.
  • Disconnect the engine harness connector 1 and connector 2 from the ECM.
  • Disconnect the engine harness from the OEM harness at the 23-pin and 31-pin OEM connectors.

Action

Inspect the engine harness, OEM 23-pin, OEM 31-pin 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.

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

Use the following procedure for general inspection techniques.
Refer to Procedure 019-361 in Section 19.

Dirty or damaged pins?
YES NO

Repair the damaged pins. Repair or 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 ICM.
  • Disconnect the engine harness connector 1 from the ECM.

Action

Check for an open circuit.

  • Measure the resistance between the ICM timing pin in the engine harness ECM connector to the ICM timing pin in the engine harness ICM connector.
  • Measure the resistance between the ICM SIGNAL reference pin in the engine harness ECM connector to the ICM SIGNAL reference pin in the engine harness ICM connector.
  • Measure the resistance between the ICM SIGNAL negative (-) pin in the engine harness ECM connector to the ICM SIGNAL negative (-) pin in the engine harness ICM connector.

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

Use the following procedure for general resistance measurement techniques.
Refer to Procedure 019-360 in Section 19.

SMALL | MEDIUM | LARGE

Less than 10 ohms?
YES NO
No Repair

Repair or replace the engine harness.

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

Conditions

  • Turn keyswitch OFF.
  • Disconnect the engine harness from the ICM.
  • Disconnect the engine harness from the OEM harness at the 23-pin and 31-pin OEM connectors.
  • Disconnect the engine harness connector 1 and connector 3 from the ECM.

Action

Check for a short circuit to ground.

  • Measure the resistance from the ICM timing pin in engine harness ECM connector 1 to engine block ground.

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

Use the following procedure for general resistance measurement techniques.
Refer to Procedure 019-360 in Section 19.

SMALL | MEDIUM | LARGE

Greater than 100k ohms?
YES NO
No Repair

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

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

Conditions

  • Turn keyswitch OFF.
  • Disconnect the engine harness from the ICM.
  • Disconnect the engine harness from the OEM harness at the 23-pin and 31-pin OEM connectors.
  • Disconnect engine harness connector 1 and connector 2 from the ECM.

Action

Check for a short circuit from pin to pin.

  • Measure the resistance between the ICM timing pin in engine harness ECM connector 1 to all other pins in the connector, and to all pins in engine harness ECM connector 2.
  • Measure the resistance between the ICM SIGNAL reference pin in engine harness ECM connector 1 to all other pins in the connector , and to all pins in engine harness ECM connector 2.
  • Measure the resistance between the ICM SIGNAL negative (-) pin in engine harness ECM connector 1 to all other pins in the connector , and to all pins in engine harness ECM connector 2.

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

Use the following procedure for general resistance measurement techniques.
Refer to Procedure 019-360 in Section 19.

SMALL | MEDIUM | LARGE

Greater than 100k ohms?
YES NO
No Repair

Repair or replace the engine harness.

Guided Step 3E – Check the ECM for active 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 459 inactive?
YES NO
No Repair

Replace the ICM.
Refer to Procedure 019-105 in Section 19.

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.

  • Turn the keyswitch OFF and wait 5 seconds.
  • Start the engine and let it idle for 1 minute.
  • Use INSITE™ electronic service tool to verify that Fault Code 459 is inactive.

Fault Code 459 inactive?
YES NO
No Repair

Return to the troubleshooting steps 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 erase 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:  22-Apr-2010
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