Yes looking for wiring diagram for 93 s10 blazer; stop light switch works; tail lights and 4 way blinkers work; and left and right signals work; but no brake lights on the rear what could be the problem??? where does the wire go from the output side of the brake light switch; trying to trace electircal path to see if ther is a broken circuit thanks herman r. williams

Could be the brake lamp switch is bad , stop lamp fuse 20 amp in under hood fuse box could be blown .Check the fuse ,if not blown check for B+ voltage at the brake switch , location - top of brake pedal under the dash . Do you know how to test automotive electrical circuit's using a DVOM - digital volt ohm meter ? Looking at a wiring diagram so you know which wires to test would be good too . Do you know what a wiring diagram is ? Free ones here http://www.bbbind.com/free-tsb Enter vehicle info. Year , make , model an engine size . Under system click on lighting ,then under subsystem click exterior lighting . Click the search button then the blue link. first diagram top left you will see the stop lamp switch . orange wire in is B+ voltage . Press the brake pedal while checking for B+ coming out on the white wire . No B+ coming out ,replace the switch . Will be other wires as well , other switch etc... check the right one .
Basic Electricity for Service Techs Ohm law Current Flow Opens Shorts
Mastering Voltage Drop Testing with Pete Meier and Jerry Truglia

You need the help of a good auto electrician because the new engine will have all sorts of sensors, switches and things to make it fire up electrically that may not have been on the old engine. Only a long look at the two vehicle wiring diagrams will sort this out.

TAIL LIGHT NOT WORKING

It can be faulty tail light bulb or its issue with tail light control switch or its wiring's are short.

Check the voltage at fuse slot of tail light.Do you receive 12 volt there.If not,then it says tail light switch is not receiving power supply.

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There are few help links related to your problem.I suggest you refer the list and check the help links.Click the link below:-----

Turn Signal Not working

http://technoanswers.blogspot.com/2012/11/turn-signal-not-working.html

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Right turn signal not working on Pontiac Car?

http://schematicsdiagram.blogspot.com/2011/12/right-turn-signal-not-working-on.html

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Only one side indicator light working on car?

http://schematicsdiagram.blogspot.com/2011/12/only-one-side-indicator-light-working.html

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Turn signals not working on 1987 Jeep Wagoneer?

http://schematicsdiagram.blogspot.com/2011/12/turn-signals-not-working-on-1987-jeep.html

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SOLVE YOUR 4 WAY FLASHER RELATED PROBLEMS HERE

http://repairhelpcenter.blogspot.com/2012/11/4-way-flasherturn-signal-flashersignal.html

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1994 Toyota Camry: Bypass Tail light Relay Circuit?

http://whatisbyme.blogspot.in/2012/04/1994-toyota-camry-bypass-tail-light.html

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2008 Toyota RAV4: Replace Tail light Lens Cover?

http://technoanswers.blogspot.in/2012/04/2008-toyota-rav4-replace-tail-light.html

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2003 Chevrolet S10 Tail light Fuse

http://schematicsdiagram.blogspot.com/2012/11/2003-chevrolet-s10-tail-light-fuse.html

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Chevrolet Parking light and Tail lamp light Wiring diagram

http://schematicsdiagram.blogspot.com/2012/11/chevrolet-parking-light-and-tail-lamp.html

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Car Tail Lights Not Working?

http://schematicsdiagram.blogspot.com/2011/12/car-tail-lights-not-working.html

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These details will help.

Thanks.

Then you need someone who can,like a repair shop

It can be faulty tail light bulb or its issue with tail light control switch or its wiring's are short.

Check the voltage at fuse slot of tail light.Do you receive 12 volt there.If not,then it says tail light switch is not receiving power supply.


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There are few help links related to your problem.I suggest you refer the list and check the help links.Click the link below:-----
1994 Toyota Camry: Bypass Tail light Relay Circuit? http://whatisbyme.blogspot.in/2012/04/1994-toyota-camry-bypass-tail-light.html

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2008 Toyota RAV4: Replace Tail light Lens Cover?

http://technoanswers.blogspot.in/2012/04/2008-toyota-rav4-replace-tail-light.html
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2003 Chevrolet S10 Tail light Fuse http://schematicsdiagram.blogspot.com/2012/11/2003-chevrolet-s10-tail-light-fuse.html
--------- Chevrolet Parking light and Tail lamp light Wiring diagram http://schematicsdiagram.blogspot.com/2012/11/chevrolet-parking-light-and-tail-lamp.html
---------- Car Tail Lights Not Working?

http://schematicsdiagram.blogspot.com/2011/12/car-tail-lights-not-working.html

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Turn Signal Not working http://technoanswers.blogspot.com/2012/11/turn-signal-not-working.html
---------- Right turn signal not working on Pontiac Car?

http://schematicsdiagram.blogspot.com/2011/12/right-turn-signal-not-working-on.html

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Only one side indicator light working on car?

http://schematicsdiagram.blogspot.com/2011/12/only-one-side-indicator-light-working.html

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Turn signals not working on 1987 Jeep Wagoneer? http://schematicsdiagram.blogspot.com/2011/12/turn-signals-not-working-on-1987-jeep.html

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SOLVE YOUR 4 WAY FLASHER RELATED PROBLEMS HERE
http://repairhelpcenter.blogspot.com/2012/11/4-way-flasherturn-signal-flashersignal.html

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Thesedetails will help.
Thanks.

It could be a bad multifunction (turn signal) switch. The way that switch works, it is possible that it can turn on the front blinker and not the rear one. It also cancels the brake circuit so the turn signal can work with the brake pedal depressed.

However, a more likely cause would be a break in the YELLOW/BROWN wire at the rear of the truck. It is common for the connector to get corroded at the left rear frame area where the bed harness connects to the vehicle harness. If you have trailer connections spliced into the wiring harness, these connections are also prime candidates for corrosion. I would look there first. Inspect these harnesses thoroughly all the way up and into the tail light assembly.

If the wires under the back of the truck look good, then I would check for power coming out of the turn signal switch. The wire at the turn signal switch is plain YELLOW (with no brown tracer). It is Pin (M) on the turn signal switch connector. The front signal is a LIGHT BLUE wire at the turn signal switch Pin (H). If you probe these with a test lamp, they should both work the same except the yellow wire will be hot with the brake pedal depressed and the switch NOT in the left turn position. If there is no power at the switch connector, replace the switch.

TURN SIGNALS WILL FEED BACK THROUGH THE TURN SIGNAL SWITCH.THEY ARE INDEPENDENT OUT SIDE ON THE CAR BUT NOT IN THE SIGNAL SWITCH.REPLACE THE SIGNAL SWITCH

could be both unrelated issues at the same time

worn indicator stalk
faulty relays

adjust or test the brake pedal stop light switch

exactly what does it do? please explain what happens when you press the brake turn on the light than brake signals ect.....

I can't look up your wiring diagram because I don't know model year?
On some makes and models, the lower brake lites are wired through the multifunction switch. Your turn and stop use the same bulb filament, just not at the same time. On a left turn, the left turn signal works, but the brake lite on the left doesn't. Now, the brake lamp on the right does work. The high mount brake lite also will work. The highmount brake lite is usually wired differently than the lower brake lites.
W/o being able to look at wiring diagram, I don't know if my info is applicable on your vehicle? I need model year.