[alfaparticle]

Will I have to use Also a Jaeger box or the Dakota replaces it?

You must use the Jaeger box with the inductive sensor that has a 3 pin connector. The Jaeger box produces 12 volt pulses that drive the speedometer. The Dakota box changes the frequency of the pulses.

 

[pbond]

OK.
Should I use the connections described in post 16 and with the post 55 notes for the newest model like mine?
As I can see from your posts, you have already connected these parts with the latest Dakota amplifier.
Any other comments?
I will also check the Jaeger amplifier for the common fault that you describe, because mine is not working also.
Thank you very much for your advise and your time.

 

[alfaparticle]

OK.
Should I use the connections described in post 16 and with the post 55 notes for the newest model like mine?
As I can see from your posts, you have already connected these parts with the latest Dakota amplifier.
Any other comments?

This is from post #55.

Dakota Digital SGI-5E
I set up the newer style Dakota Digital box today for Bruce Sharer. The wiring diagram is the same as the one in post #16 except that the red/white wire should go to OUT 1 and a 10K resistor should be connected between IN and GND. The configuration should be LO-LO and the adjustment factor that is shown when you adjust it will be about .320.

 

[pbond]

Thank you very much sir.
Now everything starts to seem clear.
I appreciate you help.

 

[dan001]

Hi Alfaparticle, I'd like to add my thanks to your efforts here, greatly appreciated.

Could you confirm one thing in case it is an oversight. For the newer dakota box, you say to connect the pink wire to output 1 instead of 3.

from your diagram, the pink wire is the switched power wire? Did you mean connect the red/white wire to output 1 (instead of 3?)

cheers

dan

 

[alfaparticle]

from your diagram, the pink wire is the switched power wire? Did you mean connect the red/white wire to output 1 (instead of 3?)

You spotted my deliberate mistake! I will correct post # 55
Thanks

 

[dan001]

glad to be able to contribute in some way

cheers

dan

 

[rowan_jackson]

A belated thank you from me too. I also used the information in this thread to set up my 1984 GTV6 with TS gearbox a few years ago. I have since had a problem and I wonder whether any of the symptoms suggest a particular cause. it has a twin spark 75 gearbox with 75 amplifier and the earlier dakota box. Sometimes the speedo works perfectly, but at other times it wildly flicks between zero and the correct speed, or reads steadily but low or simply doesn't work at all. the speedo itself has been checked by an instrument repairer who says it is fine. I have not tried changing senders or amplifiers yet largely because I don't have others which I know work.

 

[alfaparticle]

It could be a poor connection somewhere.

There is a minimum voltage for the pulse train. If the pulse are above that voltage then the speedometer reads correctly. If the voltage is low then the speedometer reads zero. There is no in between.

In my experience the amplifiers either work correctly or are completely dead.

 

[rowan_jackson]

Thanks Ed, I will have a look at the connections and see if I can spot anything.

 

[Mark_toro]

I have experienced "pulses" in the speedometer on both the Milano and GTV6 with the Amplifier / Dakota set up. For a while it seemed like they were related to brake application, then also with cooling fan. Cleaning the grounds eliminated this almost entirely. Clean grounds on these cars is important. And they are all over the place!

 

[rowan_jackson]

Thanks Mark

 

[alfaparticle]

I repaired another speedometer amplifier today for an ABB member in Singapore. It was the usual fault - blown output transistor. I believe this happens when the output wire from the amplifier to the speedometer is accidentally shorted to ground when it is turned on.

 

[Valeriy Gromov]

Hi all,
Not sure if my question meets this particular thread or not, but anyway..
Did anyone had an experience of changing cable INSIDE speedo sender?
I've got 75 TS gearbox with Jaeger box under the rear seat, but the cable that runs from sender to Jaeger box had been completly cut right near the sender, so it's almost impossible to connect to cable remainings on the sender.
Is it possible to "open" the sender to install new cable?
Thanks.

 

[alfaparticle]

I have not done that as it is still possible to find good used senders. If I had to do it I would remove some of the plastic material around the cable until there is room to solder and heat shrink a new cable. I would then fill in the hole with hot melt glue.

 

[Valeriy Gromov]

I repaired another speedometer amplifier today for an ABB member in Singapore. It was the usual fault - blown output transistor. I believe this happens when the output wire from the amplifier to the speedometer is accidentally shorted to ground when it is turned on. View attachment 1622535 View attachment 1622536 View attachment 1622537

I have not done that as it is still possible to find good used senders. If I had to do it I would remove some of the plastic material around the cable until there is room to solder and heat shrink a new cable. I would then fill in the hole with hot melt glue.

I have spare sender on 75 1,8 ie donor gearbox, but it has different type of connector (I guess later one). Are senders itself absolutely the same?

 

[alfaparticle]

Are senders itself absolutely the same?

No. There are at least 3 different ones. All of the 75's sold in the US were V6's and they all used the same sender and amplifier but the GTV6's used two different types which had 2 wires but they are not interchangeable. I think that this information is in earlier posts to the thread.
I have no idea what is in the 4 cylinder 75's.

 

[Valeriy Gromov]

I have not done that as it is still possible to find good used senders. If I had to do it I would remove some of the plastic material around the cable until there is room to solder and heat shrink a new cable. I would then fill in the hole with hot melt glue.

There was no room to solder in my case.
So I did open it..
Bad news for me, that it had oil in it.
That’s how it looks inside.

 

[alfaparticle]

That is the sender that was fitted to 1986 GTV6's in the US. Most of them have failed like yours. The Milano senders use the same circuit but it is housed in a separate "amplifier" box and the sender only contains the coil.

 

[Valeriy Gromov]

That is the sender that was fitted to 1986 GTV6's in the US. Most of them have failed like yours. The Milano senders use the same circuit but it is housed in a separate "amplifier" box and the sender only contains the coil.

Yes, this is it. I’ve got Jaeger amplifier box under rear seat, a the sender is almost blank. Just a coil.