156 RENR5042-02 Troubleshooting Section Results: E. Enable the cooling fan, if the fan is not controlled by the ECM. If the ECM controls the cooling fan, the cooling fan will start automatically when the test begins. OK The harness and wiring are OK. Proceed to Test Step 2. Not OK There is a problem in the connectors and/or wiring. F. Shut off all parasitic loads such as the air conditioning and the air compressors which could affect the results of the test. Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled. G. Set the engine speed to 1000 ± 20 rpm. H.
Select the start button at the bottom of the screen for the cylinder cutout test on Cat ET. Verify that the repair eliminates the problem. STOP. I. Select the Cylinder Cutout Test” which is the default test. Test Step 2. Check for Logged Diagnostic Codes Regarding Injector Solenoids J. Follow the instructions that are provided in the cylinder cutout test. The cylinder cutout tests are interactive so you will be guided through the procedure. A. Connect Cat ET to the service tool connector. B. Turn the key switch to the ON position. Note: The “Manual Cylinder Cutout Test” is also available. Access the manual test by selecting the “Change” button on the screen for the cylinder cutout test.
The Cylinder Cutout Test” is the recommended starting procedure. The automated tests run twice collecting data. The two sets of data are analyzed and an or “Not result is displayed. C. Check for logged diagnostic codes that are related to the injector solenoids on Cat ET. Expected Result: One or more diagnostic codes that are related to the injector solenoids have been logged. K. Check for active diagnostic codes and for logged diagnostic codes that are related to the injector solenoids. Results: OK – One or more diagnostic codes are logged. Proceed to Test Step 4. Expected Result: Not OK No diagnostic codes are logged. Proceed to Test Step 3. All cylinders indicate “OK” on Cat ET. Results:
Test Step 3. Check the Variation of the Injectors Between Cylinders OK All cylinders indicate “OK”. A. When possible, put the truck on a dynamometer. Repair: If the engine is misfiring or if the engine has low power, refer to Troubleshooting, “Engine Misfires, Runs Rough or Is Unstable” and Troubleshooting, “Low Power/Poor or No Response to Throttle”. B. Start the engine. C. Allow the engine to warm up to the normal operating temperature. If a diagnostic code results from running the Cylinder Cutout test, proceed to Test Step 4. D. After the engine is warmed up to the operating temperature, access the “Cylinder Cutout Test” by accessing the following display screens in order:
Not OK One or more cylinders displayed “Not OK” during the test. Proceed to Test Step 4. “Diagnostics” Test Step 4. Use the “Injector Solenoid Test” to Test the Injector Solenoids “Diagnostic Tests” “Cylinder Cutout Test” A. Start the engine.