Engine Speed Sensor, Checking
Function
The Engine Speed Sensor -G28- detects RPM and reference marks from a tooth wheel on the Crankshaft, without an engine speed signal, the engine will not start. If the engine speed signal fails while the engine is running, the engine will stop immediately.
Special tools and workshop equipment required
- Multimeter
- Wiring Diagram
- Scan Tool
Test requirements
- Fuses OK.
- Battery voltage OK
- Switch OFF all electrical and electronic accessories.
- Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
- Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
- Coolant Temperature: ≥ 80 °C.
- Observe all safety precautions: SAFETY PRECAUTIONS
- View clean working conditions: CLEAN WORKING CONDITIONS
Test Procedure
| Step |
Procedure |
Result / Action to Take |
| 1 |
- PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK
-- Was complaint verified? |
- NO:
- Gather more Information from customer about the complaint
|
| 2 |
- CONNECT: Scan Tool.
- START or CRANK: Engine
- CHECK: Engine RPM:
- SPECIFIED VALUE: Cranking or Idle RPM
-- Was value obtained? |
|
| 3 |
- CONDITION: May be intermittent
- PERFORM: Visual Inspection of wiring and component
- CHECK: wiring for open, high resistance, short or electrical connector for damage, corrosion, loose or broken terminals
- REPAIR: faulty wiring or connector
|
|
| 4 |
- DISCONNECT: Engine Speed Sensor -G28- electrical connector
- IGNITION: ON
- CHECK: Engine Speed Sensor -G28- wiring connector pins 1 to 2 for voltage
- SPECIFIED VALUE: About 5.0 V
- IGNITION: OFF
-- Was value obtained? |
- YES:
- REMOVE: Engine Speed Sensor -G28-.
- CHECK: sensor wheel for proper seating, damage and/or run - out.
- Sensor wheel OK
- REPLACE: Engine Speed Sensor -G28-.
- GO TO: Step 6
|
| 5 |
- REMOVE: Engine Control Module - J623-.
- CHECK: Engine Speed Sensor -G28- electrical connector terminal 1 to the Engine Control Module - J623- electrical connector T60 / 51.
- CHECK: Engine Speed Sensor -G28- electrical connector terminal 2 to the Engine Control Module - J623- electrical connector T60 / 36.
- SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω)
-- Was value obtained? |
- YES: REPLACE Engine Control Module -J623-.
- GO TO: Step 6
- NO:
- CHECK: wiring for open, high resistance, short or electrical connector for damage, corrosion, loose or broken terminals
- REPAIR: faulty wiring or connector
- GO TO: Step 6
|
| 6 |
- Final Procedure
- Perform a road test to verify repair.
- Do any DTC's return:
|
- NO:
- Repair is complete, Generate readiness code. Refer to READINESS CODE .
- Return vehicle to Customer
|