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Rut

Rut

Obi Wan
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I've installed the new wiring harness in my Bugeye and followed the Advance diagram. I've not connected the rear harness or headlights and I'm using a 5 amp fuse between the + post and the brown wire. The dash is connected and lights work as they should, but when I turn the key to the on position I blow the 5 amp fuse. This is when the regular fuse is in place between A3-A4. When that fuse is removed and placed in the A2-B position the fuse doesn't blow. Did I say that I'm really horrible when it comes to Electrickery? I understand the concept, but it's really got me buffaloed and after 2 days with a meter I'm no further along than when I started. The heater blower and switch, wiper motor and switch both work and test out ok. Help!
Thanks, Rut
 
Edit: read your post closer, now I see what you're doing. Ignore my comments...
 
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Usually the easiest way to track down such problems is to 1. understand what is being powered when the fuse blows, and 2. then start eliminating circuits until it does not blow.
The A2-B fuse is just for the horn. The A3-A4 fuse controls the heater, windshield wipers, stop lights, fuel gauge, turn signals. Note that the distributor is not fused. The idea of putting in a 5 amp fuse on the brown wire is one everyone should do when wiring for the first time!
So what I would do is eliminate one circuit at a time until you find that the 5 amp fuse does not blow. Typical problem areas: Fuel gauge not wired correctly, turn signal not hooked up correctly, or just not being able to correctly identify the wire color.
Good luck, you'll get it.
Scott in CA
 
I had a similar problem and EVENTUALLY found that I had the wires reversed on the wiper motor . It was trying to park when it was already parked. I think the 5 amp fuse to the hot wire is a good idea.
 
smaceng said:
Usually the easiest way to track down such problems is to 1. understand what is being powered when the fuse blows, and 2. then start eliminating circuits until it does not blow.
The A2-B fuse is just for the horn. The A3-A4 fuse controls the heater, windshield wipers, stop lights, fuel gauge, turn signals. Note that the distributor is not fused. The idea of putting in a 5 amp fuse on the brown wire is one everyone should do when wiring for the first time!
So what I would do is eliminate one circuit at a time until you find that the 5 amp fuse does not blow. Typical problem areas: Fuel gauge not wired correctly, turn signal not hooked up correctly, or just not being able to correctly identify the wire color.
Good luck, you'll get it.
Scott in CA
Click to expand...
Scott,
OK, I'll disconnect all the items on the A3-A4 fuse and add one at a time until the 5 amp fuse blows. The wiring diagram I'm using is this one, not Advance.
Thanks, Rut
 

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That temporary 5 amp fuse can save a new harness from disaster (all the smoke escapes and can't be put back in). Scott's method above is a good way to first fire up a new harness, really maybe the only practical way. I did about the same on my home made Prefect harness except in reverse. I added one circuit at a time and kept going until the fuse blew. I thought this might save some fuses. I got lucky and never blew one though. Either way you should find the fault fairly easily.
 
Rut
As Bugi mentioned the wipers are often an issue
I would start by unhooking the wiper motor and seeing if that corrects the issue, it is the most common mistake
BillM
 
Billm said:
Rut
As Bugi mentioned the wipers are often an issue
I would start by unhooking the wiper motor and seeing if that corrects the issue, it is the most common mistake
BillM
Click to expand...

Agree with Bill....The "D"PO of my bug eye had the wiper wired incorrectly. Its a little confusing since it is always hot and the switch provides the ground.

Kurt
 
Update: I disconnected everything and the fuse still blew...tracked it down to 1 of the 3 green wires coming off of the fuse block. Every green wire that goes to anything is taped up with no possibility of touching anything to cause a short, but the fuse still blows. Attached is a picture of the culprit. Thoughts?
Thanks again, Rut
 

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So, do you know which of the green wires is the problem?
The fuse holder could be suspect.....take the screws holding the fuse box to the chassis out, insulated the fuse holder from the chassis. Try again.
Scott
 
Scott,
I pulled the fuse holder and its in good shape and not grounded. I traced the 3 green wires to the dash and they are connected to each other by a double connector and the 'culprit' is hot at that point, key on. When the 3 green wires at the dash are disconnected from each other no fuse blows. Also, my multimeter appears to have given up the ghost and the ohm portion will no longer zero.
Rut
 
See Rut aren't you glad you put a 5 Amp Fuse in there to blow instead of the harness. Good luck.
 
So that narrows it down.....total of 5 green wires.....one goes directly to the flasher unit, another goes directly to the brake switch. That leaves three to the dash: Fuel gauge, heater, and wiper motor (feed is from the dash). I'm going to bet on the wiper motor.....it is very hard to see the marks on the motor!
Scott
 
Update #2: everything but the heater blower was wired correctly and the green/brown wire I plugged the blower into was green/black...no harm no foul. The wiper motor is the culprit and although it was rebuilt ���� and wired correctly it requires more than the 5 amp fuse to run...I even tried a 10 amp fuse and it blew just as fast. I wonder what the resistance is susposed to be? Who rebuilds these?

I also had time to check out the gas tank sending unit and it measured from 5 to 96 ohms and I hope that's correct to go with my Nisonger rebuilt Bugeye gauge.

Thanks again for the help as I muddle thru the Electrickery stage of this build!
Rut
 
Rut, when I developed my wiring for 60Frog, I check the current draw on all the components......blower motor was 3.5 amps....something is wrong with yours. Good luck Scott in CA.
 
Learned something in this thread -- and not just that I need to read more carefully first thing in the morning. The idea of the 5amp fuse to test the harness. Never would have thought of that.
 
I use a auto parts store inline fuse holder. Wires stripped back and one end under the nut on the battery cable and the other end clamped to the battery post with a hose clamp. Keeps the smoke in the wires!!:encouragement:

Kurt.
 
Thanks guys! Scott, the wiper is the one drawing the power...the blower is good to go! Any advice on a wiper rebuilder?
Rut
 
Rut, be absolutely sure yo have it wired right. As mentioned it is supposed to be wired hot and the switch makes the ground. If hooked to the wrong terminal I believe you will have a dead short.

Kurt
 
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