JBugs Video Series

1966 VW Beetle - Engine Wiring & Electrical System Testing:

Video Overview:

We’re almost done re-wiring a 1966 Beetle and with the engine installed we can finish up the wiring there and begin testing the electrical system. We did find a faulty original flasher relay so we replace that along the way. By the end of the video we will have all of the electric system working with the exception of the horn. The horn diagnosis and repair will be covered in out next video, in the meantime, follow along and watch the completion of the wiring installation!

Video Tips:

Tools used in this video:

Flat Head Screwdriver
Phillips Head Screwdriver
13mm Wrench
Wire Strippers
Test Light
Terminal Crimpers

Video Transcript:

Hi! Sam here with JBugs.com
In our last video we finished up all the wiring at the dashboard of a 1966 Beetle 
and with the firewall, tarboard, engine, and starter installed, we can finish up with the rest of the wiring.
We start with the rear of the car jacked up on jack stands, so we can access the wiring at the starter. 
Inside the car, a new battery cable grommet is installed on the positive battery cable. The cable is pushed through the floor and the grommet is pushed in place into the floor pan.
Underneath the car, the battery cable is connected to the threaded post on the starter 
along with the red power wire that goes through the firewall and to the voltage regulator. The red/black wire, with the quarter-inch terminal end, is connected to the terminal on the starter solenoid.
Now, we can go into the engine compartment and finish the wiring there. 
The engine wiring harness is routed from the left of the engine compartment to the engine, with the longer wires going to the voltage regulator. The shorter leg of the harness is routed towards the coil and oil pressure switch. The blue/green wire, in the short leg, is plugged into the oil pressure switch. The black wire is connected to the positive terminal on the coil. The longer portion of the loose, three-terminal end, black wire is connected to the positive side of the coil. The remaining terminals are routed to the carburetor and connected to the choke and the idle solenoid.
This beetle has a later model dual port engine with a 12-volt generator 
so we will have to make some modifications to the wiring there. Originally, the red wire would attach to the screw on terminal on the 6-volt voltage regulator and the blue wire would attach to the plug-in terminal.
We need to cut and strip both wires at the voltage regulator 
and crimp on a three-eighths inch terminal on the red wire and a quarter-inch terminal on the blue wire. The red wire is connected to one of the B+ terminals on the voltage regulator and the blue wire is connected to the 61 terminal on the voltage regulator.
The ends of the length of wire that we just cut off, ate stripped 
and quarter-inch terminals ends are crimped on. The red wire is connected from the D+ terminal on the regulator to the D+ terminal on the generator. The blue wire is connected from the DF terminal on the regulator to the DF terminal on the generator and then we connect the power wire from the starter to the voltage regulator. 
It is pulled from the back right side of the engine 
and hooked up to the remaining B+ terminal on the voltage regulator.
With that, all the wiring is installed so we install new fuses at the fuse box, 
hook up a battery inside the car, and begin testing the electrical system. With the battery hooked up, the dome light comes on and reaching across to both door jamb switches, with the doors open, both switches are pressed in and the light goes off. Releasing either switch turns the dome light on.
The dome light switch is moved to the off position 
and we turn the ignition key to the on position and pull the headlight knob out to the first position to check the dash lights. On the speedometer, both warning light bulbs turn on as they should. Twisting the headlight knob dims and brightens the dash lights. 
Turning the key to the start position, 
the engine begins to turn over. 
Back at the engine, when we disconnect the oil pressure switch wire 
the warning light on the speedometer goes out and the same thing happens when we disconnect the voltage regulator wire. The indicator bulbs on the speedometer are working as they should.
With a test light we confirm that the coil is getting power. 
We disconnect the wire so the coil doesn't overheat while we are testing. Back inside the car, pressing the horn button does nothing so that will have to be inspected further.
As we have the headlight knob pulled out to the first position, at the front of the car the front parking lights are on. 
At the rear of the car the running lights and license plate light are on. While we're at the rear, we'll check the brake lights which come on when the pedal is pressed and both turn off when the pedal is released. 
Operating the left turn signal, the lights on the fenders turn on but don't blink. 
We have the same issue with the right turn signal. Pulling the emergency flasher switch, the light on the knob comes on and the relay buzzes. The lights turn on in the fenders but nothing blinks. This tells us that the flasher relay is bad which isn't uncommon.
Pulling the headlight knob to the second position, the headlights come on 
and the rest of the bulbs are still on as well. 
Pressing the high/low switch on the back of the turn signal stock 
toggles the headlights from low to high and the high beam indicator on the speedometer turns on as it should. 
Turning the wiper switch knob to the first position, the wiper motor turns on. 
Turning the knob to the second position, the wiper motor goes to speed two. Turning the knob all the way to the off position, the motor operates and goes back to the parked position.
With the exception of the horn and the flasher relay, everything else in the car is working. 
The flasher relay is an easy fix as we offer a conversion relay that replaces the original 9 prong relay. 
Installing the conversion relay with all the wiring requires some of the original wiring that we just installed, 
but is otherwise quite simple.
First, we disconnect the battery. 
The original relay is removed and the wires are all pulled off. We pull the black wire from the new relay and install the black wire that went to the original relay, in its place. 
The original red wire pigtail that powered the original relay is removed from the fuse box 
and the red wire from the new relay is plugged into the bottom left of the fuse box. 
The brown and blue wires that go to the emergency flasher switch are removed 
and the brown and blue wires from the new relay are routed over to the switch and hooked up.
The brown wire goes to the S terminal, and the blue goes to the K terminal. 
The black/white wire from the conversion relay is pulled off 
and the black/white pigtail wire from the T connector is pushed on in its place. The same process is done for the black/green wire. 
The blue/green wire is removed from the turn signal indicator bulb 
and the blue/green wire from the round relay is pressed in it place. 
Finally, the black/white/green wire from the turn signal switch is hooked up to the piggyback terminal 
on the round relay.
The battery is hooked up again and with the key on, we hit the left turn signal 
and the left turn signal bulbs turn on and flash. 
We try our the right side 
and the right sire turn signals light up and flash as well. The emergency flasher knob is pulled and all four turn signals flash. We turn the key off and the flashers continue to operate as they should. The flasher knob is pressed back in. 
In the trunk, 
a zip tie is used to hold the conversion relay and flasher relay to the dashboard brace.
We'll take a break here as diagnosing the horn will take some time and work.
Thanks for watching!
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