16 replies to this topic

[Lotus man]

Trying to get the finishing bits sorted on car. I have the nylon mechanical drive in F20 box. I have the tranducer screwed onto that and I've just aquired the female plug to carry the feeds to speedo (Smiths Telemetrix). Wires are brown.....blue/red trace and black. Tried everything but not a flicker, unless something is broken (speedo is fine) what could I be missing please. I've been trying to sort this for a week now in between jobs.

Any help appreciated,
Many thanks,
Kenny

[The Matt]

Just to double check,

which way round have you got it wired?

You've got brown as earth,
Black as +ve
Blue/red as your signal wire?

Could be a faulty sensor, but does your gauge require a hall effect sensor, or a VR type one?

[Lotus man]

Many thanks for the reply Matt. I've got the thing wired up as per your post and nothing. Being an electrical numpty what are the added sensors you mention and are they a sod to fit?.....I'd give one a go if possible as I struggled to get the female plug and don't fancy rooting around for another if it's OK.............I can't see a way of checking if it's faulty though.

Many thanks for that,
Kenny

PS Following your project too.................great stuff!!!

[The Matt]

They aren't added sensors, they're types of sensors.

The VX sensor that you have is a "hall effect" sensor, I think, which will work with dashes like Acewell etc.

I'm not sure, but I think that some dashes require VR (variable reluctance) type sensors, so, if your dash requires a VR type sensor, the VX one won't work with it.

[alexcrosse]

you might need a jump up resister from the positive to the signal on your speedo.

[Lotus man]

Alex, many thanks for that, you are the second person who's said that now, I think I'll have a dabble at that first. East to get hold of and to fit?

The tech guys at Smiths say it will link up to this F20 sensor set up I have.

Thanks once more mate,
Kenny

[Lotus man]

Alex I've been informed a 2.2k resistor might do it. What is the best way of fitting this please do you know?........do I just connect it between the pulse and live wires?

Electrical numpty so apologies for the question.

Cheers,
Kenny

[alexcrosse]

on the back of the speedo just put the resistor touching the positive and signal connection (just for a tester), you can do it neater if it works! Let me no if it works or not, if it doesnt ill go and have a look at my resistor for you and tell you what rating it is, think it might just be 1k.

Cheers,

Al

[The Matt]

For reference, how many impulses do the VX sensors send per revolution? I read somewhere it is 15 per wheel rev?

[Lotus man]

Cheers Alex, many thanks. Could I do the same with the resistor down at the sensor at the gearbox end.i.e bridge the pulse and the live? Bought a pack today at Maplins as suggested to me but they are 2.2k .6v.....thinking twice about fitting these, a friend has a 1/4v one which I'll pick up tomorrow, I'll post back results.

Again thanks, much appreciated
Kenny

[alexcrosse]

just shove a 2.2 on at the speedo end and see what happens

[Lotus man]

Yesssss, I now have a working speedo After a lot of head scratching, thanks for all the input lads.appreciated.

Alex, I put the resistor on the speedo as discussed and thought all would be fine, took it for a spin and nothing........gutted!!!!

So I go's back onto speedy cables site and re-checks wiring details, stuff me I finds a red cable (named pull up) which needs to be connected if running with this type of "halls effect" sensor (in essence it only does the same job as your suggestion).

So I wire this in to ignition expecting job to be done....................nothing!!!.......gutted again.

Calls the techie guys and they say, "you never need to use this red wire with this speedo"...I was stuffed by now.
Ian at Smiths is a star though and his knowlege is superb.........he reckoned the tranducer was down, although I knew the thing was working when I fitted it, he turned out to be right.

So I decides to get meter out and go through every connection and wire on the system. Speedo would click on when ignition switch was flicked and perform diagnostics but that was that.

I had power everywhere including the plug on the transducer.............the trail stopped there so I decided on another one. Called local Vauxhall dealer and they had a brand new one in the "obsolete parts bin" I could have at a discount, luck like that never happens to me.

Goes and picks it up and fits it expecting everything now to be OK................nothing!!!!!..............couldn't believe it, well and truly stuffed.

So I connects red "pull up wire" I was told I didn't need to use................Bingo!!!!!!!!!!!!!!.....................although it did register 135mph by the time I got to the end of the road ....called Ian again and he gave me numbers to punch in to get it something like....star man.

Spent the rest of the afternoon going backwards and forwards past local flashing speed warning sign and calibrated it.......job done Pheeewww!!!!!

Many thanks again chaps for the help,

Kenny

[The Matt]

Glad you've got it working.

After reading this, I've been looking at different speedos and have decided that there are far, far better options out there than my rubbish Acewell dash. Need to make a decision which one to go for though!

[Lotus man]

Cheers Matt, thanks for that. What is the problem with the Acewell dash?, I'd heard good things about them from other lads. Hope you get it sorted mate, if you do decide to go my route I know everything there is to be known now about getting a Vauxhall transducer set and calibrated......about the only thing I do know

Best of luck with the MOT tomorrow as well, do you know the bloke testing it?....hope he's a good lad and doesn't start being an ass with log book...................fingers crossed for you and hope I read about your Pass sometime tomorrow.

Cheers,
Kenny

Edited by Lotus man, 06 August 2010 - 07:43 AM.

[The Matt]

I think the Acewell is OK, it's just a little small really.

As for the MOT. it'll be at the garage I used to work at. It'll be one of two people testing it.

Neil, who trained me up to ne an MOT tester, or Barry, who I kinda trained up. Fingers crossed, but they're pretty lenient with me normally