ELBOW-90 DEGREE 6V8628 - Caterpillar

System Operation Description:The engine speed/timing sensor provides engine speed information to the Electronic Control Module (ECM). The sensor generates a pulse signal. A loss of signal causes the ECM to stop sending power to the fuel injectors.The Electronic Control Module (ECM) provides the engine speed/timing sensor with 12 1.0 VDC. The engine speed/timing sensor provides a pulse signal to the ECM. The signal is created as the timing reference gear rotates past the pickup of the engine speed/timing sensor. The timing reference gear is mounted on the rear of the left camshaft. A unique tooth pattern on the timing reference gear allows the ECM to determine the crankshaft position, rotation, and rpm.Note: If the ring gear is reversed, the diagnostic codes 190-08 and 342-08 will be generated and the ECM will not fire the injector solenoids.
Illustration 1 g03879072
Typical example
Test Step 1. Check for Connector Damage.
Turn the circuit breaker for the battery to the OFF/RESET position.
Turn the ECS to the OFF position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Inspecting Electrical Connectors" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring are OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring need repair.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 2. Check for a CID-FMI.
Connect the Caterpillar Electronic Technician (ET).
Turn the circuit breaker for the battery to the ON position.
Turn the ECS to the STOP position.
Observe logged diagnostic codes on Cat ET. Expected Result:Cat ET indicates a CID-FMI 190-03 or 342-03.Results:
OK - Cat ET indicates a CID-FMI 190-03 or 342-03. Proceed to Test Step 3.
Not OK - Cat ET indicates a CID-FMI 190-02, a CID-FMI 190-07 or a CID-FMI 190-08. Cat ET indicates a CID-FMI 342-02, a CID-FMI 342-07 or a CID-FMI 342-08. Proceed to Test Step 4.Test Step 3. Check for Shorts in Wiring Harness.
Turn the ECS to the OFF/RESET position.
Disconnect J1/P1 from the ECM. Disconnect J1/P1 from the secondary ECM. Disconnect the primary engine speed/timing sensor J401/P401.
To test the primary engine speed/timing sensor, measure the resistance at the ECM connector P1: Measure the resistance between P1-33 and P1-51.Measure the resistance between P1-33 and P1-43.Measure the resistance between P1-43 and P1-51.Measure the resistance between P1-33 and engine ground.Measure the resistance between P1-43 and engine ground.Measure the resistance between P1-51 and engine ground.Expected Result:The resistance is greater than 20,000 Ohms.Results:
OK - The resistance is greater than 20,000 Ohms. Proceed to Test Step 5.
Not OK - The resistance is