I have a '69 SS396 4-speed I restored. I have an orginal two speed wiper and washer unit. I have the ORIGINAL wiper motor (W/M) out on my bench to trouble shoot because the motor casing was real warm all the time even when off, and smoke came from it sometimes when I ran the wipers ..

I took the thing to a guy who rewinds alternators in his garage ... and he took the motor out and said he found no short in it.

I got a bench test proceedure from and nice Technical services fella at a reman. factory in PA, and when I perform the bench test AND after 4-5 seconds of connection time, AND looking from the BACK side of the connector, smoke starts to swirl up from what looks like an inch long (ballast?) resistor when I test for HI and PARK .. .BUT does NOT smoke on LO. The resistor also looks like it just got sprayed with W-D 40 .. so I wonder if it's oil burning off ..where the oil came from I don't know.

Also I measured the AMPerge drawn putting my DVM in the 12V supply circuit and measured: LO drawing 4.5-4.6 amps, HI drawing 3.2-3.3 Amps, and PARK drawing 3.5 amps

Why is my resistor heating up so much? and should this thing be drawing current when in PARK Mode??

If anyone wants the Bench test proceedures let me know .. just means more typing

Huh! that stupid Ballast resister I believes runs parallel from one of the power inputs to ground, I've got posting re this resister as mine is "SHOT" that is rusted away and the wiper system works just fine. I think it lowers voltage throw the switch relays within the wiper motor controls. I've not received replies or confirmation as to the purpose of this resister yet.

As far as I know the wiper system should work just fine without the ballast resister because mine does - LOL. Another thing Ballast resister are designed to get HOT and Wd40 on the coils would definitely cause it to smoke until it burnt off. I do not believe that resistor has anything to do with wiper motor speed control as my wiper system works perfectly without it but I'm concerned that I may damage the point contacts of the internal relays without it.

Huh! that stupid Ballast resister I believes runs parallel from one of the power inputs to ground, I've got posting re this resister as mine is "SHOT" that is rusted away and the wiper system works just fine. I think it lowers voltage throw the switch relays within the wiper motor controls. I've not received replies or confirmation as to the purpose of this resister yet.

As far as I know the wiper system should work just fine without the ballast resister because mine does - LOL. Another thing Ballast resister are designed to get HOT and Wd40 on the coils would definitely cause it to smoke until it burnt off. I do not believe that resistor has anything to do with wiper motor speed control as my wiper system works perfectly without it but I'm concerned that I may damage the point contacts of the internal relays without it.
Wow, Thanks for the reply. Very intersting. Well then, do you know if it's normal for mine to draw 3.5 amps current when in PARK? though?

I'm REALLY interested in this thing now .. if yours works without the resistor in the game, then I wonder about it ... and sort of feel driven to find out what it's about.

I'll look into it more of it today.. Dissassemble it more and see what I can see. Plan B is I foundlast week a local shop that rebuilds "Auto electronics" ... mostly radio systems for the local car dealerships when customer's cars are out of warranty ... they'd like to see what they could find, but it'd be up to me to supply any repalcement parts if/when they did find somethign faulty.

Know anyone with a wiper motor assembly good for parts .. so far I've struck out at the salvage places around here.

.. Update - disassembling the pump cover and looking more closely at the three prong wiper motor terminal, the Ballast resistor is broken hanging on by one thin wire ... I'd like to find a new/newer three prong terminal with intact resistor and give that a try.

Good Luck finding that piece. Anyone I've come across has that Resistor rusted out. I think it could be replaced with a Carbon Unit or from say a Coil from a Dodge Ignition Ballast and attempt lower the voltage from 12 to say 6 or 8 volts for that particular Power circuit. As I say the resistor has nothing to do with Motor Speed but I believe it lowers voltage through the Relays within the Wiper Motor Control Relays to prevent arching and pitting of the contacts.

Good Luck finding that piece. Anyone I've come across has that Resistor rusted out. I think it could be replaced with a Carbon Unit or from say a Coil from a Dodge Ignition Ballast and attempt lower the voltage from 12 to say 6 or 8 volts for that particular Power circuit. As I say the resistor has nothing to do with Motor Speed but I believe it lowers voltage through the Relays within the Wiper Motor Control Relays to prevent arching and pitting of the contacts.
OK. Gotcha. Is it normal (factory spec.) the thing draws 3.5 amps in PARK (wipers off) mode on the bench test?

OK. Gotcha. Is it normal (factory spec.) the thing draws 3.5 amps in PARK (wipers off) mode on the bench test?

I don't know what you mean by this; but, if you mean the motor is drawing 3.5 amps when the wipers are in park then something is wrong as there should be no current draw in park and the dash switch is "OFF", It's likely that one of the 2 switches in the Motor Casing that control the Relays are not engaging properly to shut down the motor or you are using the wrong Dash Switch or wired to the wrong terminals.

I am certain that the Dash Switches are different for Standard Wiper System compared to the Hide-Away Wiper System.

There seems to be one mean decryption matching Dash Switches to the proper Wiper Motor for all GM 70 models as they apparently used various components and combination's that year. Sometimes reversing the Terminal Connections at the Dash Switch might work if you don't have corresponding units.

Thanks - Nice car BTW ... How do I tell if I have Hideaway wipers? (I have a '69 SS)

My ride is a 70Z I'm not that familiar with the 69 Wiper Set Up or even if the 69 had a Hide-Away Wiper Option. If you have an SS, I would speculate it would have Hide-Away Wipers. My Dad's 68 Pontiac had Hide-Away Wipers as well; that is the wipers recede below the Hood Cowl Line and can't not be seen when parked. I believe the Drivers Wiper Arm is different then the standard arm. The hide-Away System has a rod attached to the Drivers Side Wiper Arm that pivots from a different location to control blade sweep and allow a lower parking position. I also believe the Motor reverses a 1/4 turn when the Hide-Away System is Parked.

I could be wrong as I do not have a Standard Wiper System to compare it to.