John Deere 523974.04 – SFA (Front Chassis Module) or TSC (Tractor Steering Control): B167 Sensor for Oil Pressure (TLS), Voltage Too Low

The control unit detects that the voltage at the signal output of the TLS (Triple Link Suspension) oil pressure sensor (component B167) has dropped below the acceptable threshold of 0.25 volts. This indicates an issue with the sensor itself, a short to ground, or an open circuit in the wiring harness.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8245R to 8400R
• 8310RT
• 8335RT
• 8360RT
• 6230
• 6330
• 6430
• 6090MC
• 6100MC
• 6110MC

1. 1

   Locate the B167 TLS oil pressure sensor on the TLS valve block, situated between the solenoids on top of the valve (often below the radiator, opposite the crank pulley).

2. 2

   Inspect the wiring harness and connectors leading to the B167 sensor for signs of physical damage, chafing, loose connections, or corrosion.

3. 3

   Unplug the sensor on the TLS valve to see if the diagnostic reading changes or if a different code is triggered (such as a 'Voltage Too High' code), which would confirm the wiring to the ECU is intact.

4. 4

   Verify the hydraulic system is functioning correctly and providing accurate pressure to the suspension block, ruling out a catastrophic loss of pressure mimicking a sensor failure.

1. 1

   Depressurize the System

   Ensure the tractor is parked on a level surface, the engine is off, and the front axle is properly supported. Relieve hydraulic pressure from the TLS system before removing any sensors to prevent high-pressure fluid injection.

2. 2

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a broken wire or corroded connector, repair the harness or replace the pigtail connector. Clear the codes and retest.

3. 3

   Replace the Sensor

   If the wiring is intact, the B167 sensor has failed internally. Unscrew the faulty oil pressure sensor from the TLS valve block and install the new sensor.

4. 4

   Recalibrate the TLS System

   After replacing the sensor or repairing the circuit, you must use John Deere Service ADVISOR (or the tractor's onboard diagnostic monitor, depending on the model) to recalibrate the TLS system. This ensures the TSC/SFA module learns the correct voltage parameters for the new sensor.