| Author |
Message |
CarolusMax
Samba Member
Joined: July 24, 2024
Posts: 3
Location: Belgium
|
 Posted: Mon Jun 09, 2025 10:06 am Post subject: Need help with electrics |
 |
|
Dear all,
I recently converted my single carb into a Dual Carb 1600 using Weber 32 ICT carbs.
I do have questions on the electrics though. In my enthousiasm to work on amending the setup I forgot to properly mark the wiring (yes i know) I ‘m faced now with wire I’m uncertain which purpose they serve if any. (Have found some orphan wires in the car before).
Looking at the back of the car, I got a 1.5mm black wire entering the engine compartiment and getting from the same location as the one going on my coil and that has the in-line fuse. (Both entering from the back right)
Secondly I got a pair of thicker wires connected in parallel on the right side as well. This seems to be 4mm wire.
The car is currently not firing (coil is showing correct values though). Starter engine is turning the engine over.
Anyone who could help me out?
|
|
| Back to top |
|
 |
KTPhil 
Samba Member
Joined: April 06, 2006
Posts: 35900
Location: Conejo Valley, CA
|
| Posted: Mon Jun 09, 2025 11:14 am Post subject: Re: Need help with electrics |
|
|
Guessing... single with fuse holder may be for the backup lights.
2-1 coupler may be for brake lights, and is usually behind the tarboard.
_________________
Current Fleet:
- '71 Fastback
- '69 Westfalia
Retired:
- '67 Beetle
- '65 Beetle (x2)
- '65 Bus
- '71 Squareback |
|
| Back to top |
|
|
Cusser
Samba Member
Joined: October 02, 2006
Posts: 33085
Location: Hot Arizona
|
|
| Back to top |
|
|
Glenn
Mr. 010
Joined: December 25, 2001
Posts: 79504
Location: Sneaking up behind you
|
| Posted: Mon Jun 09, 2025 6:19 pm Post subject: Re: Need help with electrics |
|
|
| KTPhil wrote: |
| 2-1 coupler may be for brake lights, and is usually behind the tarboard. |
Back up lights see splice on the right of the diagram.
_________________
Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"
Member #1009
#BlueSquare
עַם יִשְׂרָאֵל חַי |
|
| Back to top |
|
|
jinx758
Samba Member
Joined: October 04, 2014
Posts: 1027
Location: half a bubble from plumb
|
| Posted: Tue Jun 10, 2025 8:33 pm Post subject: Re: Need help with electrics |
|
|
VW wiring - & most European makes :
a solid black wire is hot after the ignition/fuse box. Red is hot from battery. Brown is ground, the color of earth. Black with stripe is usually from fuse box to switch/relay & colored wires can go from switch to load.
In simple terms ... usually.
Use a simple test light to verify the thim black wire has current when ignition switch is in RUN position & no voltage when key is removed. This will go to the positive terminal of coil. Another wire on positive terminal should split to the coil and then to the carburetor solenoid if equipped or choke. A 3rd mite go to reverse switch. See Cusser's diagram above.
The only wire on negative of coil will be from condenser - tach wire goes here if equipped.
If no test light tape a wire to bottom of bulb (positive)& another to the side of base (ground). I've done this in a pinch.
Hope this helps, good luck ... stay safe
jinx
_________________
" It's not valuable unless you learn something from an experience. " Henry Ford
It's not unlike the same difference ...
My Craigslist rescued 100 footer :
1971 Standard Bug
1776cc dual port
034 distributor
38mm EGAS Carburetor |
|
| Back to top |
|
|
ashman40
Samba Member
Joined: February 16, 2007
Posts: 16573
Location: North Florida, USA
|
| Posted: Tue Jun 10, 2025 9:44 pm Post subject: Re: Need help with electrics |
|
|
| CarolusMax wrote: |
Looking at the back of the car, I got a 1.5mm black wire entering the engine compartiment and getting from the same location as the one going on my coil and that has the in-line fuse. (Both entering from the back right)
|
In the above pic of your ignition coi, it appears terminal #15 (+) is on the left. One of those black wires should come out of the wiring harness at the left C-pilar. It is powered with 12v when the ignition key is turned to ON-RUN.
The other black wire should be the reverse light power wire with the inline fuse holder?? This is typically the reverse light wire running to the reverse light switch on the front nose of the transmission.
| CarolusMax wrote: |
Secondly I got a pair of thicker wires connected in parallel on the right side as well. This seems to be 4mm wire.
|
That appears to be the L/R split for the reverse lights. The single return black wire from the reverse light switch at the front of the transmission runs to the open terminal of this junction so the power can be split into a path to the left and right reverse lights.
| CarolusMax wrote: |
| The car is currently not firing (coil is showing correct values though). Starter engine is turning the engine over. |
What do you mean by "coil is showing correct values"??? Can you provide the actual measured values and describe what you were measuring?
Place a 12v test lamp between the #1 (-) terminal of the ignition coil and a good ground point. Manually rotate the crank pulley CW with the ignition switch ON and confirm the test lamp turns ON/OFF thru two full rotations of the crank. It should turn ON 4-times. The times it turns ON is an indicator of a spark plug firing.
If the test lamp never turns ON or remains ON and never turns OFF you have an ignition problem.
Also confirm the voltage reading at the #15 (+) terminal both with the ignition switch ON AND with the ignition key in the START position. It is not uncommon to find the voltage reading is fine (12.5v) when ON, but drops below 10.0v while cranking the engine. This can be too little voltage to fire a spark.
Did you describe what this wire is for, or where it runs?
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road  }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
|
| Back to top |
|
|
|
