20 Most Recent 2002 Chevrolet Silverado 3500 Questions & Answers

Should be at the fuse block under the hood. If you have your owner's manual it explains all the fuses pretty good.

Did you do it like this? Voltmeter: black lead on negative battery terminal, positive lead on one of terminals on coil side- turn key to on, and see if there is voltage for about 2 seconds. If yes, check negative terminal of relay's coil side. If no voltage, move positive lead to other terminal for coil side. Turn key to on, and see if you have voltage for about 2 seconds. If yes, test negative side of relay's coil for good ground. If no signal at either terminal, the signal may be lost from the pcm.When you turn the key to on, this will prime the fuel system-pump will turn on for only 2 seconds with key in on, and then if no crank signal, pump will turn off (the relay will not stay energized, so no power will go to pump). But when the engine is cranking over, the relay is energized, the coil side will stay powered as long as engine is cranking. After the engine is running, usually an oil pressure switch is tied into the fuel pump circuit, so the relay is no longer needed to put power to the pump. The pump will always be running when engine is cranking, and when engine is running, but the relay no longer is needed when engine is running. See?

Should be inboard of the frame, roughly under the pedals.

did you check the oil level in the gearbox?if not enough oil it won't shift

Check spark plugs, leads, distributor cap & rotor arm, fuel pump, fuel filter, coil pack(s), relays, replace any items that are suspect IE Fuel filter which has probably not been changed since new even though they should be changed on all vehicles every 18 months, all of this can be done at home & will save you a lot of bucks in mechanic/garage fees,

have you replaced the fuel filter lately? The seal on the filter housing can be a real pain to get back on in the right location to make a good seal.

sounds like a fuel pump/sending unit.. a pump normally just quits with no warning..

Hi, I need to ask a few questions to help you. First of all, is the instrument panel lighting up when you turn the key on? If not, can you check the battery or try a jump start? After you try this, please get back to me with results for next steps.

From personal experience, You have to unplug every single plug/connector and clean up with electrical contact cleaner. This is a pain in the you know what but, In the end I found about 5 connections that were shorted out, or filled with corrosion. Try this and please let me know how you make out. Please rate answer accordingly!! Thank you

If this was not a problem before the pump replacement then the sender in the tank may of faied or is contaminated with sulfer which is corrosive to the silver electrical contacts.

Do a search on sulfur corrosion and fuel sender units. Gm has big problem with this. Its possable the stress from removing the old and installing the new pump created an issue with contacts. If this is the case you will now need a sender unit.

See GM TSB 05-08-143-001, If you have Adjustable pedals, especially if they don't work with the memeory buttons, but function with thier own buttons. Its the Brake Pedal Position Sensor is shorted and mesing up the seat module which controls the heaters too. My 05 Suburban had the same issue. Can check by unplugging switch and see if heated seats work .

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