NEED SOME HELP ON A WIRING ISSUE

gene lewis · September 13, 2009, 07:11:21 AM

Hey, Eagle owners [present or past] I need some help, please. I have a 1968, Model 05 Eagle. I have lost the brake lights.
The wiring diagrams I have from the Eagle Parts Book shows only a stop light relay with no wires attached.
This area is not a strong point of mine.
Where is the best place to start trying to locate my problem. We have turn signals and running lights -- just NO BRAKE LIGHTS.
Would really appreciate any and all assistance.
Is there a step by step procedure to follow?
Where is the brake light switch located?
Are there specific locations for terminals? If so where?
Is there anything I need to be super aware of or things to avoid?

Many thanks in advance for your assistance.

Gene

luvrbus · September 13, 2009, 07:42:46 AM

Gene, follow the yellow and green wires depending on where your 5 was made and who it was made for the switch can be at the top step on the tunnel or at the rear at the tunnel or below the drivers window where the tool box is or other places.
I installed a new one at the front where you can remove the center of blade where the Eagle emblem is and reach it check there you may get lucky.
If you need a wiring diagram ask the guys on the Eagles board to post one for you or maybe Dreamscape can post or send you one.

good luck on finding it

blue_goose · September 13, 2009, 09:30:25 AM

ON my 1968 the brake switch is in the back behind the drive axle. You need 4 foot arms to reach it and remove. I had two of them go bad because of the extra brake lights. When I replaced the second one I let it power a relay and the relay controls the lights. That one has lasted for over 15 years.

NJT 5573 · September 13, 2009, 10:19:02 AM

Gene,

For the step by step procedure you asked about, I would begin with the bulbs, (they die), and a VOM check at the sockets or wires into the sockets to be sure there is no power back there.

You can use a jumper wire on the brake light switches and find a bad one quickly that way. I have carried a couple of spares for many years, but have never lost one yet, so they aren't overly failure prone, more likely a broken wire or something along that line than a brake light switch.

You may have to do some walking back and forth to check the lights.

You also must have air to have brake lights, and someone to hold the brakes on while you check them.

I'd rather think you may have a relay issue than an air activated brake light switch. I think the relays are under the drivers side window. Trace the wires from the lights back as far as you can to be sure nothing has come loose in the back.

Its usually something easy on brake lights, so I think you will find it OK.

Dreamscape · September 13, 2009, 01:37:58 PM

Gene, Do you have the electrical schematic?

Do what NJT said, it's usually pretty simple to find. Might be a wire off on the pressure switch too, which is down under by the rear axle, at least on my 68 01 it is in that location. Ours has a lot of early 05 wiring and left over 01. I have to have two schematics to figures mine out.

Check the socket grounds too. If they are old, I'll bet they are shot like mine.

Paul

luvrbus · September 13, 2009, 02:17:05 PM

Gene, the 05 has 2 switches one for the parking brake that is located not far from parking valve if that one is bad the other one won't work check and see if your stop lights work with the parking valve.
Me I would relay it like Jack said and move it up front just follow the yellow and green wires Larry (NJT) doesn't have that luxury all of his wires are white and the switch is under his drivers window in a panel.

good luck

belfert · September 13, 2009, 04:10:26 PM

Is it normal on most buses to have the brake lights only work if you have air? I'm not familiar enough with that part of the system.

jackhartjr · September 13, 2009, 04:23:01 PM

I had BOTH brake lights burn out on my pickup last year...it does happen!
Jack

Hartley · September 13, 2009, 06:42:01 PM

Quote from: belfert on September 13, 2009, 04:10:26 PM
Is it normal on most buses to have the brake lights only work if you have air? I'm not familiar enough with that part of the system.

You know that's an excellent point.!!

I know that on my MC9 the brake lights are on even at 0 psi air pressure because supposedly there is a switch in the parking brake circuit. But there are two switches
one on the main brake air circuit and the other on the parking brake air circuit.

Once I release the parking brakes the lights go off. Apply the brake pedal they come on.
So one switch must be an N.C. switch and the other a N.O. switch. I had to change the application switch a while back and got a 5 psi switch for a freightliner and that worked perfectly.

Not sure on the Dina, They might have done similar or not...

Thanks for that thought, The old brain was failing until you mentioned that....

Dave....

Homegrowndiesel · September 13, 2009, 07:34:07 PM

Hello Gene

I hope you have good luck, After following the backwards forwards route, Good start, if not start at the front. On our 73 - 05, the power comes in on a large cable to the junction at the left of the driver (outside below window) white wire, 2 gauge ?. You have power there or else you would not have power to anything else. Test light, find the busbar that comes on when you turn on the key. (probably more than 1) Check the volts on the output of each circuit breaker on those bus bars. Several of mine were corroded and had bad contacts. On ours there was 2 separate circuits, 1 for the e brake side and 1 for the service side. Each go to a pressure switch that then run wires that go to the relay before running to brake lights at the rear. I had a bad connection at the breaker on the service side and a bad switch on the emergency side. I will check my manual and see if I can give you the wire numbers. My switches are - were up front left and right of brake pedal under floor.
Bill