Chart C Warning Lamp Comes "ON" Steady

CIRCUIT DESCRIPTION
When the ignition switch is first turned "ON" system voltage is applied from Fuse 17 to "SIR Indicator High," terminal "B9," and to the "INFL REST" warning lamp which is connected to "SIR Indicator Low," terminal "A1." Fuse 12 applies system voltage to the "Ignition 1" inputs, terminals "A3" and "B3." The DERM responds by flashing the "INFL REST" warning lamp 7 to 9 times.

When the engine is being cranked, system voltage is applied from Fuse 20 to the DERM at the "Crank" input. The DERM responds by grounding the "SIR Indicator Low" output until system voltage is removed from the "Crank" input. This results in the "INFL REST" warning lamp being "ON" during cranking.

After cranking the DERM will again flash the "INFL REST" warning Lamp 7 to 9 times.

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. An open Fuse 12 would result in a loss of "Ignition 1" voltage to the DERM. The DERM will respond by grounding the "SIR Indicator Low," CKT 358 whenever the ignition switch is "ON."
2. A disconnected DERM harness connector will cause the warning lamp to come "ON" steady via the shorting bar from terminal "A1" to terminal "B1".
3. This test checks for a short from the "SIR Indicator Low" circuit to ground.
4. This test checks for an open in the "Ignition 1" circuitry to the DERM.
5. This test checks for a short from the "Crank" input circuit to B+.
6. This test checks whether a short to ground caused Fuse 12 to open.
7. This test determines whether the short to ground is due to a malfunctioning arming sensor or a short in the wiring.