1993 Not Charging

[kirtgermond]

Hi,
My wife's 1993 4 cyl has a new alternator and a relatively new battery. Problem started with step on the brake pedal, back up lights come on, also R on the dash. Read it could be a broken wire. I will look into this.

Now dash instruments, fan, AC won't work. Fuses are ok

Now battery won't charge even with new alternator installed. I read about a fuseable link? I will look into this.

Question:
Can the wiring harness be by-passed and have a new wire run to the battery from the alternator post directly? Or is there a regulator of some sort that needs to be in between them?

Thanks for anyone's help.

Kirt

[Mike Gerber]

Check the output of the "NEW" alternator first; especially if it's an off the shelf rebuilt unit form an auto parts store. The failure rate right out of the box of these off the shelf rebuilds can be pretty high. You can check it yourself with a simple digital volt/ohmeter. Set the meter to 20 volts DC. With the car off, touch the 2 leads to the battery terminals. A charged battery will be 12 volts or slightly higher. Remember your reading. Now start the car and do the test again. You should see around 14 to 14-1/2 volts if the alternator is charging the battery properly. If you see the same reading that you had when the car was off or even slightly less, than the alternator is not charging the battery.

If you can get the car started by charging the battery from an outside source, some auto parts stores offer freee testing of the charging system with the alternator still on the car. Make a few calls to auto parts stores in your area.

Also, make sure the alternator belt is not slipping.

Mike

[chronoti]

yes you can bypass the main output line, now are you sure it's not charging or there is a large power drain? was the battery charged when the new alternator installed (dead battery tends throws the alternator wide open and blows the regulator)

look at the rear light out sensor they tend to short out giving problems, if you can set your multimeter to amp mode and see what the current draw is with the car off should be less than 500ma

and welcome to tn let us know about the fuses

[kirtgermond]

Thank you,

I will have a chance to check this out later today. The auto parts store, assuming the unit was good, checked the battery with the new alternator in--car on and off, and no change in the battery voltage. The mechanic charged the battery a bit and the car will start, so there is power in it.

I need to locate the fuseable links and check those.

It has been raining a lot here in LA and I wonder if water got in the wiring harness to short out the instruments, ac and windows?

Again, thanks for help.

Kirt