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Check Oil Indicator

The CHECK OIL Indicator lights to warn the driver of low oil level. When the Ignition Switch is first moved to RUN the Low Oil Warning Module turns on the CHECK OIL Indicator for 2 seconds as a bulb check. The CHECK OIL Indicator remains lit if the oil level is approximately 1 1/2 quarts or more low. The oil level monitoring system consists of the following components

Low Oil Warning Module
CHECK OIL Indicator
Oil Level Switch

The Low Oil Warning Module has two internal timers. One timer records the amount of time the ignition has been off while the other records the amount of time the ignition had been on before the ignition was shut off. The module uses this time information to determine if the engine has been off long enough for the oil in the engine to have returned to the oil pan.

The module will check the Oil Level Switch to determine if one of the two following conditions are met:

1. The ignition has been off for more than 32 minutes.
2. The ignition has been off for at least 3 minutes after the ignition has been on for at least 12 minutes.

If the oil level is low (Oil Level Switch open), the Low Oil Warning Module grounds the CHECK OIL Indicator, causing it to remain lit for the remainder of the Ignition cycle. The Low Oil Warning Module only checks the oil level when the Ignition Switch is first moved to RUN. It does not continuously monitor the oil level.

The Oil Level Switch is an assembly containing a read switch and magnetic float. When the oil level is normal, the float rests near the reed switch, causing the switch to close. When the oil level is low, the float rests away from the reed switch and the switch opens.

NOTE: If battery voltage is removed from and then reconnected to the Low Oil Warning Module term "F" (BAT input), the internal timers will reset. The module will behave as though the ignition has been off for 32 minutes. In this case, if the engine has been run for a time period other than one of the two listed above, the system may not check the level correctly.