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The Oil Temperature Sensor (OTS) is installed into the oil cooler housing. See Figure 24990 . The OTS sends an electrical signal to the ECM indicating engine oil temperature. The ECM uses this information to modify engine speed for better cold weather starts and faster warm-ups. Oil temperatures exceeding specification for two seconds or more will begin the stop engine or warning function. ‪

1.Oil Temperature Sensor Connector ‪

2.Oil Temperature Sensor ‪

Engine Oil Temperature Sensor

Repair or Replacement of OTS

The OTS is non-serviceable, and is replaced as a unit. No adjustment is required. ‪

Removal of OTS

Removal the OTS as follows: ‪

  1. Disengage the locking tang on the two-wire connector. See Figure 24990 .
  2. Grasp the body of the connector and gently pull it from the socket.
  3. Use the appropriate wrench on the hex portion of the sensor and unscrew it.

Installation of OTS

The Oil Temperature Sensor is an electronic device. Use care in the installation process. ‪

Install the OTS as follows: ‪

  1. Place the sensor and using the appropriate wrench on the hex portion of the sensor, tighten the screws.
  2. Use Loctite Pipe Sealer with Teflon, J 26558-92 (or equivalent) on all but the first two threads of the OTS to prevent leaks.
  3. Place the connector in the socket and engage the locking tang.
  4. Turn the ignition to the "ON" position. Observe or read any diagnostic codes. If any code other than 25 appears, refer to Troubleshooting Manual , or call Detroit Diesel Technical Service (313) 592-7282.