Thermo King SLXi Spectrum, Maintenance Manual

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Electrical Maintenance 8-21
LOW OIL LEVEL SWITCH
The low oil level switch (LOL) or oil level switch (OLS) will close and cause the reset switch to open if the engine oil level drops
below the actuation level. The low oil level switch is located in the oil pan on the front side of the engine near the oil filter.
TG-VI, MT µP-IV, µP-V, µP-VI , SR-2 and SR-3 NOTE: This switch alerts the microprocessor that engine oil level is low.
Shutdown Code 66 occurs after 5 minutes.
Switch Test
1. Make sure that the unit is turned off.
2. Disconnect the switch wires from the main wire harness.
3. Connect a continuity tester to the switch wires at the switch wire connector.
4. Check the oil level with the dipstick and make sure that it is between the low mark and the full mark. Add oil if necessary.
5. The switch should be open and there should be no continuity between the switch wires with the oil level between the low mark
and the full mark on the dipstick.
Bench test the switch if there is continuity between the 20A and CH wires and there are no short circuits in the wires.
Switch Removal and Installation
1. Disconnect the switch wires from the main wire harness before removing the switch.
2. Remove the push-in style switch by carefully prying it out of the oil pan with a pry bar. The neoprene seal may stay in the oil
pan.
3. To install the push-in style switch, first lubricate the neoprene seal and install it in the oil pan. Then press the switch into the
neoprene seal. No tools are required.
4. Connect the switch wires to the main wire harness after installing it.
Bench Test
1. Disconnect the switch wires from the main wire harness. Remove the switch from the oil pan.
2. Use a small container partially filled with engine oil to check the float. Make sure that it floats in engine oil and that it slides
freely between the upper and lower stops.
3. Slide the float up to the upper stop and check the continuity through the switch (between wire 20A and wire CH). The switch
should be open.
4. Slide the float down to the lower stop and check the continuity through the switch (between wire 20A and wire CH). The
switch should be closed.
5. Replace the switch if the float sinks or does not slide freely, or if the switch does not open and close properly.
Push-in Style Oil Level Switch
1. Connector
2. Red Wire
3. Black Wire
4. Upper Stop
5. Float
6. Lower Stop