J Type wiring

[Peter Douglas W]

Charles as I suspected, you have just confirmed that the junction is under the metal body work after the grommit. If I pull out the grommit is there enough wire to get at the bullet connector or whatever.

[johnnydog]

Peter,
You only will need to lower the rear of the gearbox slightly if you suspect any of the spade connectors may have come off the reverse light switch - this is just to gain better access to replace them, otherwise, all other checks are from above.

[Peter Douglas W]

I don't quite get that one. I can see checking the switch cables. The brown lead goes to earth and the black lead has 12V permanent. So if I pull out the grommet I presume I can get at the leads coming up from the G/B but what is that going to tell me? I do not know what is going where. I need to know if there is power on the solonoid or not. When not, under what conditions. You mean this is possible from above.

[Clifford Pope]

You have identified 12 V continuous at the switch on the gear-lever. (You mean 12 V when the ignition is on, I hope, not literally continuous?)

That's good. You don't need to know where it comes from, that bit is working.

Then operate the switch. Do you get 12v at the other terminal?

That connection goes to the 3/4 inhibitor switch, and then on to the solenoid, which should be earthed from its other terminal. Do you get 12V at the solenoid when you operate the switch, in 3/4?

Does it drop to 0 V when you move the lever out of gear?

Does the solenoid work?
If not, does it work if you take a live feed directly to it?

You don't need access to the inhibitor switch to check if it is working - just test continuity at the other, accessible end, of the wires that run to it.

When you have pinned down which component is not working, you can tackle appropriate access.

[Peter Douglas W]

Have just come back from my garage. I have just in case renewed the gear lever cables. The old cables just go to some squash type connectors (definately not Triumph bits) under the body work. Even with a mirror I have no idea where they are going. Reverse lights OK. So it looks as though I will have to get under the car to see where these dammed wires go. Before I started I bought the 2 looms, so I hope I am going to get somewhere. Years ago I saw somewhere in my paperwork/books a schematic of the circuitry with colour coding. I cannot find it any more.

[Peter Douglas W]

I have just come back from the garage 3 1/2 hours trying to put 4 electrical connecters in place. I did drop the G/B down a bit it helped a lot. I got the new looms in place using a TR6 J type logic. The colours and everything are the same. Charles just as you said the sound deadening was the cause of the accessibility problem from above. I got all the wires on, checked for the 12v, nothing at the solonoid. OK back to square one. Track back the 12 v. Nothing at the isolator switch. Strange it is a new one that was checked before being used. Once again check the connection on the switch. Suddenly it turned a little bit. I found I could turn it with my hand.Ok tightened it up a bit and I had the 12v at the solonoid. Put everything back including the skid plates and take it for a drive. "PERFECT"
Got home turned the switch a few degress nothing!!!!!!!!!!!!!! Conclusion the garage that put the G/B O/D in did not tighten the isolator switch. When the car was cold I had O/D when the car got warm the switch lost contact, when it got cold again the switch made contact. No wonder it took me so long to work that one out including a new solonoid. Thanks to everyone it is nice to have the feeling one is not alone. Also that others have had simular problems

[Mike Stevens]

You should be able to get to the lower end of the gearlever cable as it should be just below the metal surround that screws into the gearbox tunnel with 4 screws. To check the cable, pull each wire (1 brown and 1 blue I recall) in turn from each end - I.E. try to stretch it. If the copper inside has fractured, it will appear to stretch as the plastic deforms.

As all the good manuals say, reassembly is the reverse of disassembly!

I have remade them in the past by using the old connectors, resoldering them but it is a bit of a faff.

Cheers,
Mike.

[Peter Douglas W]

Mike I think you are correct.

[tony]

In my 2500's previous mode when I converted her from auto to J type I fitted a relay thinking it was the correct thing to do. I now know this is an unnecessary complication as the J type solenoid only draws 2 amps. In its present incarnation it has no extra bits, I did away with the original gear lever switch, fitted my own with proper sized terminals and have had no problems (touch wood)
Tony.

[Mike Stevens]

Although the 'J' type solenoid only draws a static current of 2A or so, the pull-in current is much higher. I reckon this will, over time, damage the gearlever switch contacts as they are pretty small. I think that fitting a relay as in the 'A' type over comes this problem.

Mind you, if you fit a better switch (as Tony has) then that should overcome it too!

Cheers,
Mike.