Author Topic: Fuse # 3  (Read 1634 times)

bwalls709

  • Full Member
  • Junior Level
  • USA, MD, Bel Air
  • Posts: 1
Fuse # 3
« on: July 11, 2024, 22:04:45 »
On my 1966 230 SL fuse # 3 blows after I put the transmission in gear. Does this mean the 3 way solenoid on top of the transmission is bad?

Cees Klumper

  • Full Member
  • Platinum
  • ******
  • USA, CA, Fallbrook
  • Posts: 5717
    • http://SL113.org
Re: Fuse # 3
« Reply #1 on: July 12, 2024, 05:29:35 »
I'd suspect an exposed wire / short before the solenoid itself, especially if it blows right away. Test to see whether you have a short somewhere along the wires.
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

BobH

  • Full Member
  • Gold
  • *****
  • United Kingdom, England, MALDON
  • Posts: 960
Re: Fuse # 3
« Reply #2 on: July 12, 2024, 07:56:46 »
Have a read on here, shows you the schematic for the automatic wiring components and colours of the wires to trace

https://www.sl113.org/wiki/Automatic/Start
February 1965 230SL Automatic
UK delivered RHD
Papyrus white, blue hard top & hub caps
Blue soft top
Blue leather

Cees Klumper

  • Full Member
  • Platinum
  • ******
  • USA, CA, Fallbrook
  • Posts: 5717
    • http://SL113.org
Re: Fuse # 3
« Reply #3 on: July 13, 2024, 02:51:47 »
You should also be able to see the 3 position solenoid working (or not) if your car has the inspection plate inside the cabin on the trans tunnel (not sure all Pagodas have this plate)..
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

lpeterssen

  • Vendor
  • Gold
  • *****
  • USA, FL, Miami
  • Posts: 666
Re: Fuse # 3
« Reply #4 on: July 26, 2024, 01:52:21 »
I think it should be something basic as the cables at the transmission terminal are not connected on the right place.

Consult this diagram and check that your cables are on the right terminal post.

Best regards
L.peterssen
Www.wiredoktor.com

lpeterssen

  • Vendor
  • Gold
  • *****
  • USA, FL, Miami
  • Posts: 666
Re: Fuse # 3
« Reply #5 on: July 26, 2024, 12:46:01 »
Dear friends

I gave it a deeper overnight thought, and I think this is what is happenning:

1. Iddle switch at intake manifold is fed through fuse no.3 with a positive signal, that passes through that switch if intake butterfly is closed, and then goes to a post in the transmission connector by cable brown /white

2. Transmission has a pressure switch that activates whenever the pressure is low. This pressure switch produces a negative signal. The cable that should be connected to it is GREEN/RED

If the brown / white cable, which carries a positive signal whenever intake throttle valve is closed, is connected to that port that gives the output of the transmission pressure switch (negative signal) you will have a instantly blowed fuse no.3

Check again terminal connections at transmission. They are definitely in the wrong position.

TRY SWAPING CABLE BROWN/white with cable GREEN/red

Best regards
Leonardo Peterssen
Www.wiredoktor.com
« Last Edit: July 27, 2024, 18:46:25 by lpeterssen »

lpeterssen

  • Vendor
  • Gold
  • *****
  • USA, FL, Miami
  • Posts: 666
Re: Fuse # 3
« Reply #6 on: August 09, 2024, 10:40:14 »
Dear Bwalls:

Any update on your electrical problem?

Try to disconnect the terminal cables at the IDDLE SWITCH and tape them.

At least disconnect the BROWN/WHITE line which carries the answer signal to the transmission.  If you disconnect this cable and the fuse no.3 stops blowing then my hypothesis was right.

Best regards
L.Peterssen
Www.wiredoktor.com