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AUTO SHUT DOWN RELAY DESCRIPTION - PCM OUTPUT The 5–pin, 12–volt, Automatic Shutdown (ASD) relay is located in the Power Distribution Center OPERATION - ASD SENSE - PCM INPUT A 12 volt signal at this input indicates to the PCM that the ASD has been activated. The relay is used to This input is used only to sense that the ASD relay is energized. If the Powertrain Control Module OPERATION - PCM OUTPUT The ASD relay supplies battery voltage (12+ volts) to the fuel injectors and ignition coil(s). With certain The ground circuit for the coil within the ASD relay is controlled by the Powertrain Control Module The ASD relay will be shut–down, meaning the 12–volt power supply to the ASD relay will be de-ac- • the ignition key is left in the ON position. This is if the engine has not been running for approxi- • there is a crankshaft position sensor signal to the PCM that is lower than pre-determined values. DIAGNOSIS AND TESTING - ASD AND FUEL The following description of operation and tests apply only to the Automatic Shutdown • Terminal number 30 is connected to battery volt- age. For both the ASD and fuel pump relays, termi- • The PCM grounds the coil side of the relay through terminal number 85. • Terminal number 86 supplies voltage to the coil side of the relay. • When the PCM de-energizes the ASD and fuel pump relays, terminal number 87A connects to termi- • When the PCM energizes the ASD and fuel pump relays, terminal 87 connects to terminal 30. The following procedure applies to the ASD and fuel pump relays. (1) Remove relay from connector before testing. Fig. 1 ASD and Fuel Pump Relay Terminals—Type 1 TERMINAL LEGEND NUMBER IDENTIFICATION 30 COMMON FEED 85 COIL GROUND 86 COIL BATTERY 87 NORMALLY OPEN 87A NORMALLY CLOSED Fig. 2 ASD and Fuel Pump Relay Terminals—Type 2 TERMINAL LEGEND NUMBER IDENTIFICATION 30 COMMON FEED 85 COIL GROUND 86 COIL BATTERY 87 NORMALLY OPEN 87A NORMALLY CLOSED 8I - 4 IGNITION CONTROL AN |