How to wire 87 blazer window switch - Belkin F1U400 Switch 4x4 USB Peripheral Windows 98 SE Me2000 XP and Mac OS 92Windows 98 SE Me

There is a relay in the under hood fuse box , blower motor relay .When switched to high it energizes the relay allowing power from the HVAC fuse /30 amp to flow direct to the blower motor. from pin 30 to pin 87 , if you look on the side of the relay there is a diagram .For all other speeds the current flows from the switch through the resistor through pin 87a to pin 30 on to the blower motor ! Check the HVAC fuse in the under hood fuse block .IF the fuse is good check for continuity between the fuse side with out B+ that means pulling the fuse and using a volt meter to see which side has power and checking the side that doesn't have power to pin 87 at the relay socket ! Probably a bad fuse or stuck relay . Pull that relay and try a different one. You can get wiring diagram at www.bbbind.com click on technical information ,then click on Technical Service Bulletins & Wiring Diagrams .then on next page go down to the bottom and click on I agree . next page click wiring diagrams ,then just fill in you vehicle information .then HVAC system . click on diagram, then you will see 7 links , click on the 5th one and that's the diagram for the blower motor circuit !

GM fusible links are always 2 sizes smaller than the wire they are in, so I think you are looking for about size 14 wire, or you could buy new links and splice them in.

https://s27.postimg.org/yy2w2qx43/starter_motor.jpg

Click on the link.
Are you talking about starter motor? In the diagram, see starter relay, unplug the relay, see terminal 30 and terminal 87, if you use jumper wire between those two terminals, the starter motor should crank, Terminal 30 is hot all the time. If you try this make sure tranny is in park or neutral and parking brake is set. If it cranks with the jumper, the problem is on control side of relay, ignition switch--neutral switch--or wiring circuit, somewhere. see crank fuse, use a test lite and voltage on crank fuse when problem is ongoing. I can only help with testing.

the one with dim power is the gas gauge,the other power wire(think it's gray) will only have power for about 3 seconds after key is switched on.
have to have an assistant turn the key while you check for power.

Are you sure the side window lockout switch located on the drivers master switch isn't on? This will kill power to the other three switches.

If your sure its not on than the I would pull the left rear window switch. There will be two dark blue wires one of them should have power all the time. If neither have power than I would pull the drivers master switch and see if there is power at the dark green wires (one will only have power with the left rear window switch in the up position.

If those are good than check the dark blue wires. one will only have power with the drivers front window switch in the up position. the other should have power all the time. If there is power there than you have a broken wire somewhere. The first place I would look is in the rubber boot in between the drivers door and the body of the vehicle.

If there is no power that the switch is bad.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

on a vehicle that old the wires are brittle start at the injector and check for cracked or broken wire in the harness

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It is likely your switch, GM switches go bad all the time. The easiest way to test this is to pull off the door panel and hook two wire directly to the motor.

Sounds like you have a wiring issue going on with one thing and the other has to do with the door itself

check starter relay

try checking for a headlight harness that belongs to the 89 and match it, or look for one online. Conversions can change the harness sometimes. You don't have to cut any wires. If you cut wires, sometimes you will have a bigger problem than you thought.