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Main Relay (Computer/Fuel System): Description and Operation





When the ignition switch is turned to the ON position, current (+15 circuit) is applied to pin 58 of the control module, which grounds pin 27 and so causes the main relay to operate. Simultaneously, pin 54 of the control module is supplied with current (+15 circuit) from pin 87 of the main relay.

NOTE: When the ignition switch is turned to the LOOK position (from the ON position), the main relay remains operated for a further 5 seconds or so if the coolant temperature is above -4°C (25°F). At lower temperatures the main relay remains operated for about 30 seconds.