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Electrical Instrument Lights / Blinker

  • Thread starter Thread starter hamirick
  • Start date Start date Jun 14, 2017
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    electrical lighting newb
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hamirick

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  • Jun 14, 2017
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Hello All,

Just picked up an 89 LX 5.0. The car seems to be pretty solid with most things working correctly. However, something that I've noticed is that the inside blinkers on the instrument panel do no flash.

The blinkers on the exterior work fine, come on, off, etc. But the instrument panel doesn't flash or blink or click. Could this be the bulb or something else? It's weird if both bulbs are bad.

As a side note, the wipers do not work, so I have a new multi-switch coming this weekend for that. Related, maybe???

Thanks!
 
Last edited: Jun 14, 2017

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Jun 14, 2017
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Was this originally a v8 lx
 
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hamirick

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EDITED ORIGINAL POST TO MAKE SENSE.

I just pulled the VIN and it actually was a v8 so disregard the conversion comment.
 

General karthief

wonder how much it would cost to ship you a pair
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#4
  • Jun 14, 2017
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It is possible for both bulbs bad, but like you said, unlikely, do you know if the cluster has ever been changed?
I would pull the cluster and check the bulbs and you can test for power to them then.
Will they light up when you hit the 4way flashers? They probably won't but can't hurt to try.
Without looking at a wiring diagram it maybe possible the problem is in the multifunction switch, but I'm just guessing there.
See if they work after you change the switch.
 
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Mustang5L5

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28 year old car....plenty of time for bulb to burn out
 
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hamirick

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  • Jun 14, 2017
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Cluster looks original, speedometer/odometer doesn't work (cable issue, not cluster) and mileage is exempt on title. The cluster does look like it's all original. I've not pulled the back to check the print board. I'm going to get some 194s tonight and pull it, but didn't know if anyone had any ideas.
 

General karthief

wonder how much it would cost to ship you a pair
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#7
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I've always got ideas, rarely are they any good!
 
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hamirick

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Jun 21, 2017
#8
  • Jun 21, 2017
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So, it was the multi-switch and a bulb. I changed the multi-switch and the left indicator worked fine. Pulled the cluster, changed the right bulb, and now they both work fine!

Thanks all!
 

General karthief

wonder how much it would cost to ship you a pair
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#9
  • Jun 21, 2017
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And another satisfied customer.
what are you gonna do now?
 
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hamirick

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#10
  • Jun 21, 2017
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Figure out the issue with the wipers. Getting power in the fuse box, so I have a new 6a breaker delivering today. I also have a new wiper motor, so i'll try both options tonight.
 

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hamirick said:
Figure out the issue with the wipers. Getting power in the fuse box, so I have a new 6a breaker delivering today. I also have a new wiper motor, so i'll try both options tonight.
Click to expand...

Windshield wipers – how it works theory and operation

Multispeed windshield wiper operation

The wiper motor does not have a resistor pack inside it. It does have one armature brush offset from the other two and a cylindrical permanent magnet instead of a set of field coils. The two brushes directly opposite each other are the low speed brushes. The low speed brush works in conjunction with one of the high speed brushes to provide a second speed.

Self Parking mechanism:
The self parking mechanism is copper circle glued or stuck on the wiper gear. The circle always has 12 volts on it until the wiper comes to the park position. There are two copper spring switch contacts, one provides power to the copper circle, while the other provides a path to the low speed winding. The power contact always provides power to the copper circle except when in the park position. The low speed contact is always in contact with the copper circle. When power is turned off at the wiper control, the 12 volts continues to flow to the low speed motor brush until the wiper blade returns to the park position.


Interval Governor:
The interval governor is a fancy electronic switch that sends the motor a pulse of electricity that varies in duration time. It always runs on the slow speed motor brushes. Turn the wipers on and quickly turn them off. The self parking mechanism inside the motor makes sure that the wiper blades come back to the park position and stop there. The interval governor does the same thing: it sends power to the wiper motor and then turns it off. The duration of the pulse sent to the motor determines how many strokes it makes before stopping at the park position. If you watch carefully, you will notice the wiper blade speed is constant and never changes when you are using the interval wiper function.

Troubleshooting:
All tests done with the ignition switch in Run or Accessory position and wipers on.

1.) Look for constant 12 volts on the red wire on the wiper motor. No 12 volts, the fuse is blown, bad wiring or bad connection. This will cause park problems or no wiper operation
2.) Check the ground. No ground and nothing works, bad ground and you get intermittent operation.
3.) No high speed operation, low speed OK. Look for 12 volts on the Dark Brown/orange wire. No 12 volts, bad wiper switch, bad connections or bad wiring.
4.) No low speed operation, high speed OK. Look for 12 volts on the white wire. No 12 volts, interval governor faulty or missing, or bad wiring. Since this is a pulse and not a steady voltage, a test light used in parallel with the voltmeter may be a better indication of operation
5.) Motor low speed test: Jumper the brown/white wire on the interval governor to the white wire. The motor should run in low speed mode. I haven’t tested this yet, so use caution. If the motor does not run, the low speed brush may be bad.

Do all this and by that time, maybe I’ll have figured out some simple tests for the interval governor…

See http://www.popularmechanics.com/cars/how-to/maintenance/how-to-fix-your-windshield-wiper-motors-2 for more help.
 
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hamirick

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#12
  • Jun 21, 2017
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Dude.. wow! Thanks for the help!

I just replaced so I have a new 6a breaker in the fuse box, new multi switch, new wiper motor and still no wipers. I'm going to see if the red wire has power or not. If not, I'm going to trace back the issue between the motor and the fuse box.

Thanks again!
 
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hamirick

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Jun 21, 2017
#13
  • Jun 21, 2017
  • #13
So, red is getting 12v. I created a good clean ground, nothing. Checked both motors. Nothing.

Internal Govenor appears to be completely shot. Case is busted up and board looks luke it's been tampered with. The red cable for it is getting 12v though.

Sigh. Guess I'll look for one of these in the junk yard now. From checking around, even without the internal governor, I should still have high speed function, right? Because I dont. I wonder if my parts guy grabbed a 90 multiswitch rather than 89. Could that be the issue?

I don't want to keep throwing money at it.

Thanks.
 

General karthief

wonder how much it would cost to ship you a pair
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Jun 22, 2017
#14
  • Jun 22, 2017
  • #14
Post the part number for the old mf switch and the brand/part number for the new switch.
 
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