A Free Trick To Help Speed Up Your Power Windows.

Ive Found A Way To Speed Up (and Repair What Was Thought To Be Bad Motors)for Gm's Power Windows Over The Years Doing My Electrical Work .
Heres A Few Tricks Ive Learned That Works And Is Free.the #1 Cause Of Failed Power Windows (other Than Switches Or Wiring) Is Not The Motor Its Self,but A Thermo-load-resistor That Is Inside The Power Window Motor.its Located In The End Of The Housing Where The Harness Plugs Into The Motor From The Switch Controls.over Time They Fail,and The Least Amount Of Load And The Window Stops And/or The Speed Decreases.
I'm Going To Show How To Bypass The Resistor,and Some More Basic Maintenence To Speed Those Slow Windows Up.
Ive Had Requests For Instruction On How To Do This Mod,but No Pics Until I Had To Do This To My 1994 Gmc Safari Van Today.i Had The Opportunity To Perform This Mod,and Since This Vans Pw Motor Is Identical The The Regals,gave Me The Opportunity To Post This Thread.
Any Questions About This Mod,please Ask.here We Go....

Tools/parts Needed;

Small Piece (6") Of At Least 16 Ga Wire
3m T Tap (blue)
Male Spade Connector (blue)
Small Ring Terminal (blue)
Test Light/ohm Meter
Electronics Cleaner
Small Pic
Spray Grease
Good Crimpers
30 Amp Blade Fuse (green)

Heres A Pic Of The Motor Out Of Door.

A Pic Of The Cover On The Connector Side Of The Motor (some Motors Has This Cover,some Do Not).it just snaps off.

Heres A Pic Of The "test Port".this Is Used (WITH A VOM,TEST LIGHT)To See If Voltage Is Passing Through The Load Resistor.if Battery Equivalent (within 1-1.5 Volt) Is Found In This Test Port While Pushing Window Switch To Run Motor Being Tested,the Wiring,resistor,etc Is Good.stop Here And Replace Motor.

If Voltage Is Not Sufficient At The Plug On The Motor,check Switches,grounds,and The Circuit Breaker In The Fuse Box.

if theres good voltage at the motor plug,but not at the resistor test port,the resistor is faulty and this mod will definitely help .

What We Are Going To Do Is Inject Voltage Past The Resister Using The "test Port".

The Resistor Only Protects One Of The Two Wires That Come From The Switch To The Motor.this Is Why We Will Only Have To Jump Voltage For One Wire/lead.

Heres A Pic Of The Jumper Harness Assembled.

Here Is The Jumper Wire Terminal Connected By A Small Screw Through The Test Port. The Test Port (if You Could See Inside The Housing)is The Metal Flat End Of The Resistor With A Small Hole In It.the Screw Penetrates Through This Hole To Make The Connection.

The Jump Lead Will Now Connect To The Wire (in My Vans Case,blue.) That Has Positive Voltage As You Command The Window Motor Up.

(one Wire Will Show Negative,and The Other Will Show Positive Going Up.)

If You Command The Window To Come Down,the Voltage Polarity Will Swap And Change To The Opposite.this Is Called A Five Wire Reverse Polarity System.this Also Is Why If One Switch Goes Bad For The Passenger Window(they Are Wired In Series) That It Will Not Work.

You Can Also Test With A Vom.the Terminal That Has 0 Ohms (NOTICE METER IS NOT QIUTE SHOWING 0ohm,I COULDNT HOLD THE METER PROBES AND THE CAMERA AT THE SAME TIME,THUS THIS HIGHER READING)To The Test Port Is The Wire You're Going To Tap Into To Bypass The Resister.the Other Terminal Should Show 1-2 Ohms Depending On The Condition Of The Motor.

Heres A Pic Of The Correct Way To Use A T Tap.you Can Solder,etc. But If You Strip Back The Insulation On The Wire,and Use The Correct T Tap For The Gage Of Wire,you'll Have A Very Solid Connection.ive Used These For Years.they Are Fast And Just Snap Onto The Wire Without Any Perminate Modifications To The Harness.

Tip #2.............THIS IS JUST, IF NOT MORE IMPORTANT THAN THE RESISTOR MOD......before The Next Step.nows The Time To Clean And Tighten The Terminals On The Motor,plug From Switch To Motor,window Switches And Their Plugs,and Lube The Regulator With A Very Generous Amount Of Grease.while You're At It,lube The Door Look Linkage,rods,etc And The Lock/latch Assemblies From The Inside....

Pic Of Clean,tight Window Motor Terminals

Pic Of Jumper Harness Installed,motor Connected.test Motor Before Installing For Operation. You Wont Be Able To See Any Difference in torque or speed Until The Motor Is Installed.

the load resistor is a safety device that disconnects power incase a switch shorts (stays in the up or dowN posistion,OR SOMEONES ARM GETS CAUGHT,ETC)or motor overloads,or any harness or mechanical failure.
take the power window circuit breaker out of the fuse block and replace it with a fuse identical amperage rating.incase of a sort (the CB will keep trying to reconnect voltage) now instead,the fuse will blow and you'll know to check the system.

secure the jumper harness to the original wiring out of the regulators way.reinstall motor,test before final assembly of door panel,etc.

well i dont have to help my window up anymore :biggrin: ....or roll it up two inches At time .
its never been faster,and I'm willing to bet if i went and replaced this motor with a brand new delco,it wouldn't keep up (it comes with the good ole resistor too ).
also, its always best to have car running while operating the windows,the increased voltage from the alternator means that it takes less amperage for the motor to do their job.run car even when rolling down the windows because while rolling down the window,the motor also has to load the helper spring.

HTH Gary.

A VERY GOOD SUGGESTION and yes an extra ground wire run through the boot to the grounding point in the door at the same place where the switch grounds would help out.

good ground from battery to body is important.
tight terminals in the fuse block,good ign switch,alt charging above 13volts (at idle),etc all help.

Great info, Thanks!

I'm an ex-GM service tech too....they always blame problems on any type of modification or connector that isn't factory.(and understandably so,theres no license or test for anyone to work on cars)
Techs Aren't as savy as the past (low experience because of the automotive repair field and the employee turn over rate) and they train techs to shy away of "unproven" methods.(you must follow the computer or the tech 2 steps)
as in ANY part,connector,accessory,etc there a wrong and right way to use.Ive used 3m t-taps for over 10 years on very high amperage applications like remote starters,etc with no problem. the key is the correct one for the gage of wire,and stripping the insulation for 100% contact.

heres a link to 3m page about the t-tap.

i don't however like the "Scotch lock",except the largest version (brown 10ga +) because it has double contacts for each lead.


3M eStore: 3M Scotchlok T-Tap Nylon Insulated Self-Stripping Female QuickSlide Disconnect 952X, 18-14 AWG

grab a couple to test a few to see the results for yourself.you can find them at autozone,orlies,etc...they have became popular.


another point to add; use high quality (3m) male spades to plug into the t-tap.they are thicker and make a better contact/connection inside the t-tap.