steerig wheel controls

I suppose that channel up is 473 ohms and channel down 203 ohm, and not vice versa as you wrote?
If that is correct then you have correct values, expected from switches of that kind.

Actually values should be 0 ohms, 82 ohms, 202 ohms and 472 ohms, but you have some additional resistance from wires in the loop.
There are two additional switches with different resistance values from above. One have 6 switches other 4 switches.
Their values are 0 ohms, 390 ohms, 860 ohms and 1k68 ohms for volume down, volume up, channel down and channel up.


What I see here is that your controls do not correspond to radio head unit you used. Your controls actualy do what they should. Volume up and down are in range of 2-83 ohms which is both lower then 390 ohms and because of that they both do only volume down. Channel switch up and down are 202-472 ohms which are in range of 390 ohms which is volume up. Your switches are way low for any channel change.


You can either look for replacement switches or you can try to add additional resistor for switches to come into above ranges.


Did you try your switches on all three (3) head units you have?

Same issue with my 25

I'd exactly the same result as you @jensden51 when two years ago I retrofitted steering wheel control in my 25.

You helped me finding the right bunch of wires (maybe some compatible with BMW I don't remember, but anybody could have a go in the appropriate thread in the ZR / 25 section at http://forums.mg-rover.org/mg-zr-ro...steering-wheel-remote-control-pioneer-807946/) @Roverlike because I couldn't get anything at all, and thanks to that I'm glad now to be able to get the up / down result for the volume.
I can live with that even it would have been more gratifying to get it working entirely right.

But for the sake of the truth and not to die idiot I would be grateful to learn the how to do it correctly even if it's a bit too late: the 25 is now my better half's car and she doesn't care even of the steering wheel volume control! :lol:

I have a little bit of confusion with your naming. When you say the one with ISO connector you used pins 10 and 17.
I assume that is Blaupunkt CD/Radio XQE100380? If so that radio does not have ISO connector but BMW 17-pin connector. However, pins used are correct 10 and 17.
Second head unit is I suppose VDO unit 79DC631 and connectors you call "rover" connectors where green plug is used are actually ISO connectors (A, B and C; green connector is middle part of ISO C connector). Also jn this case pins 11 and 12 are used which corresponds to correct pins.


In case of XQE100380 seems that you have Rover branded model which does not have pins 10 and 17 in use. If I am correct only MG branded XQE100380 have these pins used. Your model uses K-bus and expects K-bus signal on on pin 7. In order to be able to use that you would need another module in between your steering wheel controls which will convert resistance signal to K-bus signal for the radio. This module is YWQ100031. I can provide you wiring if you would like to go into this route. You would need to use steering wheel controls from R45 with higher resistances you measured.


In case of VDO unit, I cannot tie it to be used as factory fitted to any MG-Rover. If that is true, then you most probably will need to use Autolead adapter in order to get it runing. Which Autolead adapter you need I can tell if I kjow which connectors you have in your car? I suppose ISO A and ISO B?

Roverlike said:

I think that in your case you also have steering wheel controls with different resistances then the one expected. You most probably need other one of two we mentione here. Problem is I do not know/remember which one you have? You would also need to measure resistance on the switches.

Problem is that if you are buying second hand switches you cannot know which one are for sale as you do not have resistance measured from breaker side.

Click to expand...

The problem is I don't remember either more than anyone can see in the thread I've given the link of. It sends us back two years and a half back! All the pictures but the two first are in place and that PC99-X32 you advised me to fit.

Regarding the switches, I didn't bought them by chance from nowhere, I bought an entire genuine used Rover 25 steering wheel in good order with its controls attached on.

Hence I haven't still any clue to understand why the connection is only half functioning.
Judging by what you've just told in the previous posts, I guess that the problem might be that the PC99-X32 wasn't the perfect solution. Am I wrong?
That's indeed the only bit that bridges the wires coming from my genuine Rover 25 steering wheel and my Pioneer Bluetooth radio multi-plug and wires as shown in the pictures below:
http://forums.mg-rover.org/mg-zr-ro...ontrol-pioneer-807946/index2.html#post8304601

Dorchester said:

The problem is I don't remember either more than anyone can see in the thread I've given the link of. It sends us back two years and a half back! All the pictures but the two first are in place and that PC99-X32 you advised me to fit.

Regarding the switches, I didn't bought them by chance from nowhere, I bought an entire genuine used Rover 25 steering wheel in good order with its controls attached on.

Hence I haven't still any clue to understand why the connection is only half functioning.
Judging by what you've just told in the previous posts, I guess that the problem might be that the PC99-X32 wasn't the perfect solution. Am I wrong?
That's indeed the only bit that bridges the wires coming from my genuine Rover 25 steering wheel and my Pioneer Bluetooth radio multi-plug and wires as shown in the pictures below:
http://forums.mg-rover.org/mg-zr-ro...ontrol-pioneer-807946/index2.html#post8304601

Click to expand...

Without Autolead adapter PC99-X32 you would not have any movement on the radio whatever you press on the switches.
What I want to say is there are at least two types of steering whell audio controls with different resistance values provided when you press your switches.
Problem is they all look the same from outside and if you are seeking for second hand one you do not know what are you buying.
Only difference in these switches is resistance you need to measure. If you are buying new ones, you do know by the part number.

When you bought steering wheel with switches attached you will get what you get. Breakers will not measure resistance on switches and you will not know what you are buying. Point is, you can buy several Rover 25 steering wheels with switches attached but you still can get all the same type of switch. You have better chance to get other type if you buy Rover 45 steering wheel.

Now when I passed through old thread most likely you also have steering wheel switches with resistance values same as OP and most probably you need higher knes as described in this thred.

However you need to be certain in one thing: when you try to put radio from 2018 in a car with steering wheel switches from year 2000 or 1995 you are just trying to get as best as you can. Manufacturers use their standards for head units and you might win or may not. There is not only one standard with head units and steering wheel switches. There are many throught years.


Only in case if you got head unit and steering wheel switches from factory you know for sure they will work. Anything else is experimenting and trying to gst as good as you can.


Even MG-Rover needed to use different standards for different headnunits and different resistance on switches from period to period.


So in your case you might try to get your hands on steering wheel switches with higher resistance values from R45 and see if you will get volume and channel controls as they should be.


PC99 adapter just converts resistance to other type of signal needed for newer type of head units, nothing else. If resistance is not of proper value, converted signal will not be of proper value for desired action. That is all.


Old Philips units called R770 or R870 which were radio-cassette units used in Rover 200 R3 and Rover 400 from 1995 were the ones which could use lower set of resistance values without any modifications.