WHEEL (Impeller) 1T0022 - Caterpillar

Use this procedure to troubleshoot the electrical system if a problem is suspected with the passive sensors. Or, use this procedure if one of the following diagnostic codes is active or easily repeated.
Table 1
Diagnostic Trouble Codes
J1939 Code and Description Conditions that Generate the Code System Response
105-3
Engine Intake Manifold Temperature 1 : Voltage Above Normal The ECM detects signal voltage that is greater than 4.95 VDC for 8 seconds. The code is logged.
The value of the parameter is set to a default value.
105-4
Engine Intake Manifold Temperature 1 : Voltage Below Normal The ECM detects signal voltage that is less than 0.2 VDC for 8 seconds.
110-3
Engine Coolant Temperature : Voltage Above Normal The ECM detects signal voltage that is greater than 4.95 VDC for 8 seconds. The code is logged.
The value of the parameter is set to a default value.
110-4
Engine Coolant Temperature : Voltage Below Normal The ECM detects signal voltage that is less than 0.2 VDC for 8 seconds.
175-3
Engine Oil Temperature 1 : Voltage Above Normal The ECM detects signal voltage that is greater than 4.95 VDC for 8 seconds. The code is logged.
The value of the parameter is set to a default value.
175-4
Engine Oil Temperature 1 : Voltage Below Normal The ECM detects signal voltage that is less than 0.2 VDC for 8 seconds. System OperationUse this procedure to troubleshoot any suspect problems with the following sensors for the primary ECM:
Coolant temperature sensor
Intake manifold air temperature sensor
Engine oil temperature sensor
Illustration 1 g03382025
Schematic of the analog sensor signal circuit
Illustration 2 g03382032
Terminal locations at the P1 ECM connector for the passive sensors
(P1-26) Engine oil temperature
Illustration 3 g03382037
Terminal locations at the P2 ECM connector for the passive sensors
(P2-17) Common Return
(P2-83) Common Return
(P2-84) Engine coolant temperature
(P2-95) Intake manifold air temperature
Illustration 4 g01155187
Terminal locations at the connector for the passive analog sensors
(Terminal 1) Sensor signal
(Terminal 2) Sensor return
Table 2
Troubleshooting Test Steps Values Results
1. Check for "Active" or "Logged" Diagnostic Codes
A. Connect Caterpillar Electronic Technician (ET) to the service tool connector.
B. Restore the electrical power to the ECM.
C. Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes.
Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
D. Determine if the problem is active and related to one of the following diagnostic codes:
-3
-4
Codes
Result: No diagnostic codes are active at this time.
Repair: The problem may be intermittent. If the problem is intermittent refer to Troubleshooting, "Electrical Connectors - Inspect".
Result: An active -3 diagnostic code is present.
Proceed to Test Step 2
Result: An active -4 diagnostic code is present.
Proceed to Test Step 4
2. Check for a Short to the +Battery at the Sensor Connector
A. Measure the voltage on the harness side of the sensor connector between pin 1 and pin 2 for the suspect sensor.
+Battery
Result: The supply voltage is less than Battery voltage.
Proceed to Test Step 3.
Result: The supply voltage is equal to Battery voltage.
Repair: There is a short in the harness to the +Battery. Repair the wiring.
Verify that the repair eliminated the problem.
3. Create a Short at the Sensor Connector
A. Turn