Low Oil Level Warning System - Description/Operation
83ford5 Article No. 83-24-6WARNING LIGHT - LOW OIL LEVEL WARNING SYSTEM - DIAGNOSTIC INFORMATION
FORD 1984 T-BIRD, LTD, CROWN VICTORIA
LINCOLN-MERCURY 1984 COUGAR, MARQUIS, GRAND MARQUIS, CONTINENTAL, MARK VII, LINCOLN TOWN CAR
Figure 20:
The low engine oil level warning system is used as standard equipment on 1 984 Continental, Mark VII, and Lincoln Town Car, and as optional equipment on 1984 T-Bird/Cougar, LTD/Marquis, Crown Victoria/Grand Marquis with 3.8L and 5.0L engines. The schematic (Figure 20), diagnosis, and testing information has been updated to assist the technician.
Figure 18:
Figure 19:
This system consists of a float type sensor mounted to the side of the engine oil pan, an electronic control module, and an instrument panel warning lamp (Figures 18 and 19). The warning lamp should come on during engine starting as a bulb prove-out. When the ignition switch is turned to the Run position, the control module determines whether the sensor is grounded (oil low) or ungrounded (oil not low). If the oil level is approximately 1.4 liters (1.5 quarts) or lower, the relay turns the warning lamp on. The lamp remains on until the ignition is turned off. After the ignition is turned off, the module will not reset for approximately 90-150 seconds. The delay allows time for oil drainback before another reading is allowed to occur. If the engine is restarted during this delay period, the last reading will be displayed.
Major Components and Function
Sensor
^ Located horizontally in the side of the oil pan.
^ Is normally open electro-mechanical float-type device.
^ When oil level is low (approximately 1-1/2 quarts), the float drops and closes the electrical circuit to the relay.
^ The connector to the sensor is a new "push-pull" design.
Control Module Location
^ Located as shown in the chart.
^ Features an integral timer that delays closing the relay for about 90-150 seconds after the ignition switch is turned off.
^ The timer feature minimizes possible false readings that may occur when the engine is restarted without sufficient time for oil to drain back into the oil pan.
Car Line Nomenclature Location Electronic Relay Locations
T-Bird/Cougar Check Oil Warning Lights R.H. side of steering column
Panel on I/P bracket
LTD/Marquis Check Oil Warning Lights R.H. side of steering column
(upper tier) on I/P bracket
Mercury Grand Check Level In cluster R.H. lower reinforcement
Marquis of I/P
Continental Check Oil Warning Lights R.H. side of steering column
Panel on I/P bracket
Lincoln Town Low Oil Level Warning Lights R.H. lower reinforcement
Car Panel of I/P
Mark VII Check Oil Warning Lights R.H. lower reinforcement
Panel of I/P
Warning Lights
^ Momentarily glow when ignition switch is turned to "start" as "prove-out" that bulb is working.
Figure 18:
Figure 18: Low Oil Level Warning Lamp
Description and Features
^ Sensor in oil pan signals indicator light on instrument panel when oil level is low (approximately 1-1/2 quarts).
^ This system does not replace the oil pressure warning system.
Sensor Test Connect positive lead of a VOM to sensor terminal and negative lead to sensor housing with sensor submerged in oil (engine full). Meter should read "open" (greater than 100,000 ohms). With sensor out of oil (oil drained), resistance should be less than 4,000 ohms.
NOTE: Sensor must be horizontal when this test is conducted. It is best to conduct test with sensor in pan with hot oil to assure that oil properly drains from sensor. If removed from pan, sensor must be submerged in warm oil first to assure proper orientation of the float before testing. The sensor must be held horizontally during bench testing to assure that the float remains correctly oriented.
Removal and Installation
Sensor
Removal and Installation
1. With engine off, drain at least 1.9 liters (2 quarts) of oil from engine, 2. Disconnect electrical connector.
3. Remove sensor with a 26 mm socket or end wrench.
4. Reverse Steps 1 through 3 for installation.
NOTE: Whenever it becomes necessary to remove the oil level sensor from the oil pan, make sure that when replacing it, the following torque values are used:
When replaced using all plastic gasket, torque to 25-35 ft.lbs.
When replaced using plastic with rubber O-ring gasket, torque to 20-30 ft.lbs.
Figure 19:
Figure 19: Low Oil Level Sensor
Bench Check of Sensor
^ Connect positive lead of VOM to sensor terminal and negative lead to sensor housing.
^ Hold sensor in horizontal position to assure proper orientation of the float.
^ Submerge sensor in warm oil to assure that oil properly drains from the float area of the sensor.
^ With sensor submerged in oil (engine full), meter should read at least 100,000 ohms.
^ With sensor out of oil (oil drained), resistance should read less than 4,000 ohms.
Diagnosis and Testing
System Check
^ Oil must be a "full" mark on the dipstick, and "hot" to assure that oil properly drains from float area of the sensor.
^ Turn on ignition and start engine.
^ Warning light should come on with ignition in start (prove-out) then go off.
^ Drain two quarts of oil from the oil pan.
^ After a delay of approximately 150 seconds, turn ignition on and start the engine.
^ The warning light should come on and stay on.
Troubleshooting Hints
Does Not Operate
^ Check fuse.
^ Check low oil level relay.
^ Check low oil level sensor.
Adjustments
^ There are no adjustment procedures.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"
TEST EQUIPMENT: VOM
LIGHT STAYS ON AFTER STARTING ENGINE - OIL NOT LOW