Speed Pulse Connection

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ralft01
Joined: Mon 02 Jun, 2014 09:00
Posts: 37

  Z3 roadster 2.8

Speed Pulse Connection

Post by ralft01 » Wed 21 Oct, 2015 20:02

Help please! I bought a Pioneer radio , 2002 vintage, which has satnav built in, but which requires input from the vehicle sensors. It is a handsome piece of kit, and I like the idea of a satnav in the radio, even though the only disc produced for the system is based upon pre-2000 roads.
It looks nice and works well as a radio and CD player, but to fire up the satnav I need to connect one of the leads to a vehicle cable carrying speed pulse data, and I have no idea how to proceed. Any help, advice or comments will be very gratefully received.

Hairyscreech
Joined: Thu 16 Apr, 2015 13:08
Posts: 69

  Z3 roadster 2.8

Re: Speed Pulse Connection

Post by Hairyscreech » Thu 22 Oct, 2015 22:49

What kind of signal does it need? You should be able to take one off the diff sensor for the dash or the ABS sensor. The OBC has a speed signal from the clocks as well.

What Z3 are you fitting it to?

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Speed Pulse Connection

Post by pingu » Thu 22 Oct, 2015 23:18

If you calibrate it yourself, you could try one of the ABS sensors.

[Edit] Daft idea. Use the speedo sensor.
Pingu

ralft01
Joined: Mon 02 Jun, 2014 09:00
Posts: 37

  Z3 roadster 2.8

Re: Speed Pulse Connection

Post by ralft01 » Fri 23 Oct, 2015 07:48

Thanks for the suggestions. I guess that to get to the speedo sensor cable I need to remove the instrument panel? I read somewhere that if I do that I have to have the unit recalibrated!
How would I identify the correct cable, and would it be OK to connect a another cable to take the speed pulse to the radio? I think the radio needs an analogue signal.
This is for my 1998 Z3 2.8

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Speed Pulse Connection

Post by pingu » Fri 23 Oct, 2015 09:13

ralft01 wrote:Thanks for the suggestions. I guess that to get to the speedo sensor cable I need to remove the instrument panel? I read somewhere that if I do that I have to have the unit recalibrated!
How would I identify the correct cable, and would it be OK to connect a another cable to take the speed pulse to the radio? I think the radio needs an analogue signal.
This is for my 1998 Z3 2.8
Pulses from ABS or speed sensors are either 0 or 1.

See page 203 of this : http://www.porterbility.co.uk/Files/PDF/e36z3_98.pdf

Brown/Black (BR/SW) is nominally 0v
Brown/Red (BR/RT) is the signal wire. Its voltage will fluctuate as the rear wheels are spun.

Without disconnecting anything, I would probe the two wires and spin the rear wheels to see if the needle of an analogue voltmeter moves. It may be too small (or quick) for a digital meter, but if that is all you have, give it a go. If it does fluctuate, bingo. (You could do this at the rear of the car. The speed sensor is at the rear of the diff.)
Pingu

siwilson
Joined: Fri 19 Jun, 2009 10:54
Posts: 782

  M roadster S54
Location: Horley

Re: Speed Pulse Connection

Post by siwilson » Sat 24 Oct, 2015 08:46

There is a speed signal on pin 10 of the radio connector. It is called the GAL signal and it is how the standard BMW radio gets louder when you go faster. Pin 10 is not usually populated in the BMW to ISO adapter, so you will have to connect it directly. The best way would be to add a pin to to your adapter cable. Nice and clean that way. You can get the connector from BMW. Part #9 on the diagram.

Search for GAL, it has been discussed on here before.

Si.
2001 M roadster S54 Laguna Seca Blue

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Speed Pulse Connection

Post by pingu » Sat 24 Oct, 2015 12:43

siwilson wrote:There is a speed signal on pin 10 of the radio connector. It is called the GAL signal and it is how the standard BMW radio gets louder when you go faster. Pin 10 is not usually populated in the BMW to ISO adapter, so you will have to connect it directly. The best way would be to add a pin to to your adapter cable. Nice and clean that way. You can get the connector from BMW. Part #9 on the diagram.

Search for GAL, it has been discussed on here before.

Si.
Excellent info. I'll put this in the memory bank - and then forget how to find it :D .

See page 243 of this : http://www.porterbility.co.uk/Files/PDF/e36z3_98.pdf

The route of the wire depends on whether you have Karman Kardon fitted. The Black/White (SW/WS) wire comes from the instrument cluster. If not fitted, the wire goes to the back of the radio (Pin 5). If fitted, it goes to the amplifier (Pin 1).
Pingu

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Robert T
Site Admin
Joined: Mon 12 Jun, 2006 11:35
Posts: 9984

  Z3 roadster 1.9
Location: Cheshire

Re: Speed Pulse Connection

Post by Robert T » Sat 24 Oct, 2015 19:05

More info here: http://www.zroadster.net/forum/viewtopi ... &hilit=gal

I actually linked to this in my previous reply, where I asked ralf to start a new thread if he had more questions.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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