821306A18 Mercury GEAR HOUSING

Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
105-3 Inlet Manifold Temperature Sensor voltage above normal The engine's Electronic Control Module (ECM) detects signal voltage that is more than 4.8 VDC for one second.
The ECM has been powered for at least three seconds. The code is logged.
The value of the parameter is set to zero.
105-4 Inlet Manifold Temperature Sensor voltage below normal The ECM detects signal voltage that is less than 0.2 VDC for one second.
The ECM has been powered for at least three seconds.
175-3 Engine Oil Temperature Sensor voltage above normal The ECM detects signal voltage that is more than 4.8 VDC for one second.
The ECM has been powered for at least three seconds. The code is logged.
The value of the parameter is set to zero.
175-4 Engine Oil Temperature Sensor voltage below normal The ECM detects signal voltage that is less than 0.2 VDC for one second.
The ECM has been powered for at least three seconds. System OperationUse this procedure to troubleshoot any suspect problems with the following sensors:
Inlet manifold temperature sensor
Engine oil temperature sensorThe sensor signal for the passive sensors is routed from the ECM to the connector for the right rail. The sensor signal is then routed to terminal 1 of each sensor connector. The sensor return for the passive sensors is routed from the ECM to the connector for the right rail. The sensor return is then routed to terminal 2 of each sensor connector.
Illustration 1 g01242605
Typical schematic
Illustration 2 g01242612
P1 ECM connector
(P1-3) Sensor return (left rail)
(P1-14) "Inlet manifold temperature sensor"
(P1-26) Engine oil temperature sensor
(P1-35) Sensor return (right rail)
Illustration 3 g01163206
Sensor connector
(Terminal 1) Sensor signal
(Terminal 2) Sensor return
Illustration 4 g01234146
Location of ECM connectors
Test Step 1. Check for "Active" or "Logged" Diagnostic Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Restore power to the ECM.
Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes. Note: Wait at least