Does it make any sense to anyone why i am only getting 4volts on my multitester when hooked up to the connector where it goes into the wiper motor? I been down the whole road of checking:
fuses,broken wires,modules,resoldered any cold joints on wiper motor,batt connections..i think i have tried all.I even made sure that when hooked up to the battery direct the wiper motor works just like normal,so wiper motor is good.I am sure this problem is somewhere between the firewall and where in goes to wiper motor.This is a 1995 Blazer & i just installed a NEW multifunction switch,as my hazard broke,but it was 4volts BEFORE the installation,as i thought it was probably fried anyhow.

 

I'm away from home and don't have access to service manuals -- but---
there has to be a relay between the multifunction switch and the wiper motor. Otherwise all that wiper motor current would have to go through the multifunction switch.
Find that relay and you'll find the problem; either crummy contacts inside the relay or in the socket. I'll look for the relay location in my manual upon return in a few days. Anyone else??

 

What a hero if any relays are found Mammy's car!!
Weird how now that i got the new multiswitch in,now i have no radio or overhead consel
functions. Right now i unhooked batt for 1hour to see if some reset is a ticket out of this nightmare.

Update:
Unsuccessful.
Even tore open stereo dash section to see if there's any fuses,relays.Nothing.Thus far i was better off with having only the hazard switch broken,now i got hazards and no stereo/overhead consol.

 

No relay. It's all inside the motor housing "Windshield Wiper Motor Module" where control voltage from the multifunction switch manipulates the heavy current coming from the fuse.
My 2000 service manual shows during pulse or low speed operation a variable voltage fed from the multifunction switch to the wiper motor module via the gray wire 112, some voltage less than 12 fed via the dark green wire 113, and 12 volts via the purple wire (high only). Ground is via the black # 850 wire. The heavy current carrying yellow wire 143 always has 12 volts from "FRTWPR" fuse 17. It's possible that your '95 has different colors, fuse numbers, etc.
The wiper motor module is inside the wiper motor housing and is replaceable.
When you measure 4 volts, is it on the 'yellow' lead (probably heavier wire than the others except for ground)? You should have solid 12v on this heavy lead with the key in Acc or Run.
If not, it's the wiring as you suspect. If 12v is there, try the module.

Edit; Blazer got home and I checked out the actual wiring arrangement. The 3 voltage leads appear to be the same gauge (size) with the black ground being slightly larger. Fuse 17 is in the end of the dash board, not in the engine compartment fuse box.

 

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What a respectful reply!!

I know it is probably not totally clear where my voltage issue is mammy's Car.
I am only getting that 4volts WHERE the wiper connector plugs INTO the wiper assembly to run the wipers.When i hook it directly to battery(not connected to the connector coming from inside of dash) with my own wires, Then wipers have NO issues at all.
The problem is somewhere between where the multiswitch and where it goes into the wiper motor.I hope all that makes sense.

Could you reveal what you mean by 'Engine compartment fuse box'? Is there one inside the engine area i'm over looking?
P.S. My 95 has the wiper fuse as Fuse#11,if that at all matters.

P.S.s I have hooked up a entirely different wiper motor,with the same 4volt issue and non functioning situation.
Your help is heavenly regarded!

 

Any final 'helps' before i take this lil pig in to stealership?

 

Did you check the ground for the wiper motor? When you tested the voltage, was it with the wiper motor disconnected or with it connected and you back probing the wires?

 

Thanks Swartllk,it only showed 3-4volt incoming from the wire where it clips into wiper motor.BUT after finding a nice dude who charges $30/hr,the problem is now extinct.
It was the ignition switch and $200 later stereo,overhead consol & wiper/washer have me and my 'lil pig' back on he raging roads again!

 

Glad you got it fixed!