DTC 522655-0 - Short Term Closed Loop Correction Bank 1 Less Than NOR -40% (Rich Engine
Operation)

CAUSE B - PROBLEMS THAT MAY CAUSE RICH ENGINE OPERATION
PROCEDURE OR ACTION:
1. Common problems that may cause rich codes:
* Clogged/dirty air filter
* Fuel quality (Very high butane content)
* Operation at high altitudes
* High primary fuel pressure (for trim fuel injector)
* Faulty trim fuel injector or wiring
* Faulty LPG carburetor (power valve stuck open)
* Faulty LPG regulator
* Manifold vacuum leaks
* Improper ECU grounds on engine block
* Faulty ECU injector driver 2

2. If DTC continues to be displayed after examining/correcting the above, go to Cause C.

CAUSE C - SENSOR FAILURE
PROCEDURE OR ACTION:
1. Ensure truck power is OFF.
2. Replace sensor.
NOTE: Do not discard original sensor after removal.
3. Ensure that all connections are completely inserted.
4. Turn truck power ON.
Does reported DTC reoccur?
YES: Reinstall original sensor and go to Cause D. See Electrical System 2200 YRM 1142.
NO: Problem has been corrected. Resume operation. Discard faulty sensor.

CAUSE D - FUNCTIONAL FAILURE IN CONTROLLER
PROCEDURE OR ACTION:
1. Ensure all previous procedures have been completed.
2. Ensure truck power is OFF.
3. Ensure that all connections to the controller are completely inserted.
4. Ensure truck power is OFF for no less than 30 seconds, and then to ON to clear displayed DTC.
Does reported DTC reoccur?
YES: Go to Step 5.
NO: Problem corrected. Resume operation.
5. At the DSC, press ENTER to access Main Menu.
6. Scroll to VIEW VERSIONS, press ENTER.
7. Scroll to TRUCK SERIAL NUMBER, press ENTER.