Home page
SPONSOR AD SPONSOR AD

Topic: Testing continuity

in Forum: C3 Electrical


Testing continuity

Posted: 1/24/06 10:09pm Message 1 of 18
Lifetime MemberLifetime Member
Send PM
Canada
Joined: 8/6/2004
Posts: 533
Vette(s): Coupe 74 - 454 Drive it like you stole it!
 
I had a thread in "interior" (chose the wrong category by mistake) concerning a power window problem (which I still have).
 
Here's the thing; I could find it so much faster myslef (not that I don't appreciate all the help I get here...) if I knew how to diagnose electrical probems.
 
So, 2 questions:
-Is there a good book out there for electrical dummies like me who would like to educate themselfs about the basics of electricity/electronics ? (And not necessarely related to cars/vettes; I recently built a full size arcade and I had many problems there too... and still do!)
 
-Concerning the power window; I did a continiuty test at the circuit breaker and at the switches (well, detached from the actual switch; I inserted the leads into the holes of the female part that connects to the PW switch.  Both test were positive (good).  At this point, I have to assume that the wiring is good and that both motor and/or PW switches wouldn't go bad on me at the same time.
 
Is it possible that my problem is that I'm trying to pull the windows back up while the key is on accessories only ?  I have seen some post here where people with similar problems had to have the engine running at a fairly high RPM to get the window running.
 
 



SPONSOR AD:: (Our Sponsors help support C3VR)

Testing continuity

Posted: 1/25/06 7:01am Message 2 of 18
Lifetime MemberLifetime Member
Send PM
Westerly, RI - USA
Joined: 5/26/2005
Posts: 133
Vette(s): 77 L48 Original paint True dual stainless exhaust Edelbrock intake manifold and Thunder series carb Distributor has an pern upgrade

I'M NO BETTER THAN YOU WITH ELECTRICAL PROBLEMS BUT I CAN TELL YOU I HAVE A STRONG BATTERY AND ON ACCESSORIES BOTH WINDOWS GO UP SLOW AND THE DRIVERS SIDE NEEDS COAXING NEAR THE TOP WHILE WITH THE ENGINE RUNNING THEY BOTH GO UP FAIRLY SMOOTHLY.

GOOD LUCK




Testing continuity

Posted: 1/25/06 12:21pm Message 3 of 18
Former Member
Send PM
Virginia City, NV - USA
Joined: 1/19/2005
Posts: 314
Vette(s): 1979 Coupe, white in color

I don't know if they have a "Electronics for dummies" book, but I got one when I first got my electronic Keyboard, called "Playing electronic keyboards for dummies" it was pretty good. Check your local library for books on electronics, they must have some basic concept books. In addition to being ASE certifed master at one time, I've been to electronics school for computers, worked for Mallory Ignition, and am a licensed Amateur radio operator, and I still don't sail through electrical problems, just the nature of the beast.   If I were the one checking the problem, I would start at the begining, with testing the battery with a volt meter, then move to the fuse panel and check to insure no voltage drops, check the fuse for being burnt out, then check the supply to the switch, then power on the motor side in both directions. Where ever the power stops befor the motor is where I would look first.

Dave

Pumps38742.5156365741


Testing continuity

Posted: 1/25/06 12:40pm Message 4 of 18
Limited Member
Send PM
Newark, DE - USA
Joined: 7/26/2004
Posts: 468
Vette(s): 1968 Conv, 454HO,500HP-600TQ, TKO-600,3:70 HD rear,hotrod air, custom paint & suspension,1973 Ruby Red,T-top, 383 Stroker, TK)-500,frame off restro, 1967 Dodge Coronet, 340 stroker to 406, Dana 60

I would suggest taking a night course on basic electricty. It will cover all tha basics, then you understand how electricity flows & reacts with different components. After thgat it'll all come together...even house wiring. I send new techs who don't know about electricty & they've all come back with a pretty good base to start diagnosing problems.

Alan




                                               

Testing continuity

Posted: 1/25/06 3:04pm Message 5 of 18
Former Member
Send PM
Davie, FL - USA
Joined: 2/29/2004
Posts: 173
Vette(s): 1980 l48
 I use a "Petersons" Basic auto repair manual. It has most of the stuff that the other manuals leave out because they think we already know it. ( I don't)  Mine is number six published in 1974 works for most the stuff on my 80. You might find one in a used book store or even Petersons might be able to get you an older one.


Mike

Testing continuity

Posted: 1/25/06 3:50pm Message 6 of 18
Lifetime MemberLifetime Member
Send PM
PERRYSBURG, OH - USA
Joined: 4/23/2004
Posts: 317
Vette(s): 1975 T-Tops,Lite Custom work,Many engine mod. 700R4 trans. body is shaved,17" wheels bf goodrich g-force tires,heavy sway bars front&rear rack&pinion steering,550 slolom springs with gas shocks.
Can't Help much myself. Everytime I do some thing with 12volt systems I have to scratch my head and take a few steps back. I find asking for help works just as you have. I'm sure there is someone here that can help. I know my windows run pitty slow on my vette. I just figured the motors are old? Sorry can't help futher.


Testing continuity

Posted: 1/25/06 3:58pm Message 7 of 18
Former Member
Send PM
Joined: 12/16/2003
Posts: 630

I think I would have to echo what others have said. If you want to learn electricity, particularly controls, circuits, schematics, you need to start at the beginning. Check out your local junior college and see if they don't offer courses. You will not learn this stuff from a book, it takes hands on in a lab set up to simulate various problems that you need to use a meter to diagnose. Having a qualified instructor to coach you and help you to learn how to figure out the problems at hand is priceless. Don't look for a course that is maybe 2 or 3 nights, it won't happen. This will take a committment from you to finish the program, probably a year or more of 1 night a week.

By the way, SLOW windows are often caused by lubrication breakdown of all the moving parts in the window mechanism. How often do people take their doors apart to clean and re-lubricate all those parts? 

Big Fish38742.6674421296


Testing continuity

Posted: 1/26/06 8:49am Message 8 of 18
Lifetime MemberLifetime Member
Send PM
Canada
Joined: 8/6/2004
Posts: 533
Vette(s): Coupe 74 - 454 Drive it like you stole it!
Update : last night I took the door apart and hot wired the pw motor to my battery charger.  I've set it to 12v 6amps.
 
Got a little spark from it, a little bit of noise, but nothing to make it go up; which is fine by me, because now I know that I didn't burn both pw motor at the same time.
 
Just in case there was not enough juice straight from the battery when the engine is off and key is on accs, I took it for a spin (about 15 minutes) and kept on trying.  No noise, no click, no nothing...
 
I then tested the pw motor for 12v using a multimeter and holding the switch up/down..... Nothing!  (which is also good news).
 
The only thing I haven't found yet is the pw relay which I think is somewhere under the shifter console; top/left and possibly linked to the heater/wiper wiring.  I already replaced the circuit breaker which was cracked.
 
I guess I will also make a trip to Borders and find a book to start educating myself.  I co-worker recommended the community college which is about a mile from here.  I'll find out what kind of classes they have.



Testing continuity

Posted: 1/26/06 3:56pm Message 9 of 18
Lifetime MemberLifetime Member
Send PM
North Charleston, SC - USA
Joined: 3/20/2004
Posts: 4176
Vette(s): 1975 L48 AT AC T-top
I would suggest getting a multimeter that tests for volts as well as ohms. They are inexpensive and priceless for tracing down the problem. I would start by putting the meter on volts(20v)position on the dial. I would start at the PW switches to see if I had 12 volts coming to the switch. If yes, then the switches are the problem, although it is highly improbable that both are bad. If you don,t have voltage to the switches then the problem is probably the relay which I believe is under the console. If you keep working toward the primary power source you will eventually find the bad component or "open" in the wiring.

You can also use the meter in the ohms or resistance mode to find broken wires or loose connections. Perhaps a wire has been pinched or rubbed raw allowing the conductor to "short" to ground. That will smoke circuit breakers, fuses, and relays. I would also invest in a shop  manual that has a schematic of the wiring circuits. They are not that difficult to follow and with the meter you will be able to hunt down the varmint.

Good Luck,
Scott



Testing continuity

Posted: 1/26/06 5:13pm Message 10 of 18
Former Member
Send PM
Joined: 12/16/2003
Posts: 630

Ranger 3 is on target, but I thought I might add a few safety tips if you are going to buy a meter.

1.  The cheap meters will work for you, but you must remember that when the meter is set for "ohms" or "continuity" and you use it to check voltage the meter will be dumpster material in most cases.

2. When checking volts, always start with a voltage scale that is higher then the anticipated voltage you might expect to find. Pegging the needle by using too low of a scale may cause the meter to be dumpster material

3. When working with cars you must be careful of the "polarity" when using a cheap meter. The black wire is ground, the red wire is positive, and reversing the polarity may cause the cheap meter to be dumpster material when the needle pegs on the wrong side of the scale.

If you decide to spend maybe a 100-150 bucks on a good meter, you will find they are a lot safer to use and will not sustain damage from improper use. Fluke makes a very nice meter that is digital and won't cost more then about $125. You will usually get what you pay for with a cheap meter.




in Forum: C3 Electrical


SPONSOR AD: (Our Sponsors help support C3VR)