Tracker 101: intro to the relays
 

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The 2001 Tracker has fourteen relays. Twelve of them are Single Pole, Single Throw (SPST). Only two -- the door LOCK and
UNLOCK relays -- are Double Throw (SPDT). Thirteen of the relays are available under alternate part numbers. The Rear
Defogger relay is discontinued although several Chevrolet dealers claim to have one on the shelf (for $100)

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The A/C compressor relay is located on the relay rack under the hood.

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The A/C condenser fan relay is right next to it..

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The HVAC blower motor relay is behind the glove box.

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The door lock relay is under the dash, left-center.

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The door unlock relay is right next to it.

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The fuel pump relay is on the junction block.

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The main (aka fuel injection or FI) relay is right above the fuel pump relay.

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The headlight relay is mounted on the Junction block.

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The tail light (aka headlight #2) relay is found below the headlight relay.

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The horn relay is located on the relay rack under the hood.

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The Oxygen Sensor heater relay is located on the fender near the windshield washer bottle.

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The rear defogger relay is found under the dash to the left of the junction block.

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The flasher relay is the one you never want to go bad. Although alternate part numbers
are available, it's near impossible to replace. Note the picture above is step ten in the
removal process. The prior nine steps describe unbolting the junction panel from the
bulkhead. The flasher relay is not even visible when it's installed.

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The only was to locate it is to find the white connector (C5) under tail light relay
and turn on the emergency flashers. Reach one finger behind the junction panel
where the white connector is and feel for a small clicking box. That's the flasher relay.