R042

CIRCUIT DESCRIPTION
During the "Turn-ON" tests, performed at the beginning of each ignition cycle, the DERM delays charging of the "Driver 36 VLR" terminal "A4" and "Passenger 36 VLR" terminal "A3" power supplies. After the delay has expired both "36 VLR" power supplies are allowed to charge. The DERM monitors each "36 VLR" power supply to ensure each has charged to a voltage above a specified value within 10 seconds after "Ignition 1" voltage is first applied to the DERM. When either "36 VLR" power supply does not reach the specified voltage within the allowed time or, once reaching the specified voltage, falls below it for 500 milliseconds, DTC R042 is set.

DTC WILL SET WHEN
The voltage at either "36 VLR" power supply does not exceed a specified value within 10 seconds after "Ignition 1" voltage is first applied to the DERM or, once having reached the specified value, either "36 VLR" power supply voltage falls below the specified value for 500 milliseconds. This test is run each ignition cycle at "Turn-ON" to detect a charge time failure and, after charging, tested every 100 milliseconds during the "Continuous Monitoring" tests.

ACTION TAKEN
DERM turns "ON" the "AIR BAG" warning lamp and sets a diagnostic trouble code.

DTC WILL CLEAR WHEN
The voltages measured at "Driver 36 VLR" terminal "A4" and "Passenger 36 VLR" terminal "A3" are above a specified value for 500 milliseconds.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks whether the DERM has set the diagnostic trouble code falsely.
2. This test checks whether a malfunctioning dual pole arming sensor is preventing the "Driver 36 VLR" or "Passenger 36 VLR" from charging.
3. This test checks for a short from the "Driver 36 VLR" or "Passenger 36 VLR" circuit to B+.
4. mis test checks for a short from the "Driver 36 VLR" or "Passenger 36 VLR" circuit to ground.

DIAGNOSTIC AIDS
An intermittent condition is likely to be caused by a short from "Driver 36 VLR" or "Passenger 36 VLR" to B+ or ground, or a malfunctioning dual pole arming sensor.