C7.1 Engines and Generator Sets Caterpillar


Exhaust System Contains Fuel

Usage:

C7.1 770

Probable Causes

  • Short circuit in the ARD fuel pump relay wiring

  • Corrosion in the wiring harness connectors for the ARD fuel pump relay

  • Failed ARD fuel pump relay

Recommended Actions



Illustration 1g06143030
ARD fuel pump schematic

Complete the procedure in the order in which the steps are listed.

Carefully following this procedure is a good way to identify wiring problems.

Table 1
Troubleshooting Test Steps  Values  Results 

1. Inspect the Components

A. Visually inspect the components for the ARD fuel pump system. Look for the following problems:

1. Loose connections or damaged connectors

2. Moisture on the connectors or the wiring

3. Damage that is caused by excessive heat

4. Damage that is caused by chafing

5. Improper routing of wiring

6. Damaged insulation
 

Damaged Wiring or Connectors 

Result: There is a problem with the wiring or a connector.

Repair: Repair the wiring or connector. Replace parts, if necessary.

Proceed to Test Step 4.

Result: The wiring is OK.

Proceed to Test Step 2.
 

2. Check for Voltage at the Coil for the ARD Fuel Pump Relay

A. Turn the keyswitch to the OFF position.

B. Measure voltage between the relay coil and a good ground source.

There should not be voltage on the relay coil when the keyswitch is in the OFF position. Low amounts of voltage can keep the relay pulled in after the keyswitch has been turned to the OFF position.
 

Voltage 

Result: There is voltage between the relay coil and a good ground source.

There may be a short from a power source in the wiring harness. There may be moisture or corrosion in a connector between the ECM and ARD fuel pump relay coil.

Make the necessary repairs.

Proceed to Test Step 4.

Result: There is not voltage between the relay coil and a good ground source.

Proceed to Test Step 3.
 

3. Check for Voltage at the Load Side of the ARD Fuel Pump Relay

A. Turn the keyswitch to the OFF position.

B. Measure voltage between the load side of the ARD fuel pump relay and a good ground source.
 

Voltage 

Result: There is voltage between the load side of the ARD fuel pump relay and a good ground source.

Remove the relay. Check for voltage between the load side of the ARD fuel pump relay and a good ground source.

If voltage is present, there is a short in the wiring between the relay and the ARD fuel pump. Repair or replace the wiring.

If voltage is not present, the relay has failed.

Repair: Replace the relay.

Proceed to Test Step 4.

Result: There is not voltage between the load side of the ARD fuel pump relay and a good ground source.

For further assistance, confer with the Dealer Solutions Network (DSN).
 

4. Clean Fuel from the Exhaust System

A. Remove excess fuel from the piping with a clean cloth.

B. Inhibit regeneration with the inhibit switch.

C. Operate the engine at elevated idle (1500 RPM) for 20 minutes.
 

Excess Fuel 

Result: The excess fuel and white smoke did not return after operating the engine for 20 minutes.

Repair: Perform a Manual DPF Regeneration using the electronic service tool.

Return the unit to service.

Result: The excess fuel and white smoke returned after operating the engine for 20 minutes.

Contact the Dealer Solutions Network (DSN).
 

Caterpillar Information System:

992K Wheel Loader Systems Pressure Switch (Steering Cooler Filter Bypass) (Steering Pump Case Drain Filter Bypass)
980L Tier 3 Wheel Loader Engine Supplement Engine Oil Cooler - Remove and Install
C7.1 Engines and Generator Sets Exhaust System Contains Coolant
980M Tier 4 and 982M Tier 4 Wheel Loader Engine Supplement Engine Oil Cooler - Remove and Install
992K Wheel Loader Systems Piston Pump (Implement, RH)
AD22 Underground Articulated Truck Oscillating Hitch - Lubricate
994K Wheel Loader Machine Systems Seat - Remove and Install
AD22 Underground Articulated Truck Oscillating Hitch - Adjust
A New Valve Mechanism Cover and Elbows Are Now Used on Certain 3412, C27, and C32 Machine Engines {1107} A New Valve Mechanism Cover and Elbows Are Now Used on Certain 3412, C27, and C32 Machine Engines {1107}
MD6310 Rotary Drill Air Compressor Oil Filter - Change
MD6310 Rotary Drill Air Compressor Oil - Change
950 GC Wheel Loader Power Train Transmission Oil Cooler
980L Tier 3 Wheel Loader Engine Supplement Engine Oil Filter and Oil Filter Base - Remove and Install
C7.1 Engines and Generator Sets Exhaust System Contains Oil
980L Tier 3 Wheel Loader Machine System Piston Pump (Implement) - Remove and Install
C7.1 Engines and Generator Sets Fuel Consumption Is Excessive
C7.1 Engines and Generator Sets Fuel Contains Water
C7.1 Engines and Generator Sets Fuel Rail Pressure Problem
C7.1 Engines and Generator Sets Fuel Temperature Is High
980L Tier 3 Wheel Loader Machine System Piston Pump (Implement) - Disassemble
C7.1 Engines and Generator Sets Inlet Air Is Restricted
MD6250 Rotary Drill Air Filter Elements - Clean/Replace
980L Tier 3 Wheel Loader Engine Supplement Expansion Tank - Remove and Install
C7.1 Engines and Generator Sets Intake Manifold Air Pressure Is High
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.