Guys Using PAC Steering wheel interfaces.. question
I'm having an issue with the steering wheel controller, and I don't think the PAC SWI-PS is the way to go.
In my x-type I used a PAC SWI-X (the universal remote one) and I had this same problem. Apparently our Jags have a weird issue when it comes to the steering wheel controls. They use stepped resistance, which the swi series controllers read fine, BUT apparently the resistance changes when the headlights are on, and the buttons are illuminated.
SO what happens is, when you program the SWI-PS with the headlights on, the vol up / down and track up / down buttons work ONLY with the headlights on. If you program with lights off, it only works with the lights off.
ON my X-type with the swi-x I actually developed a workaround, where I programmed the buttons with the lights on, and lights off seperately. The SWI-X is just a learning remote, so it didnt care what code it sent. i.e. you could make every button volume up.
The SWI-PS, however has a specific sequence with which you have to program it. And I don't think there is a way by which you can assign multiple buttons (which the SWI series perceives the vol and track buttons as different with lights on or off) to the same function.
I am thinking about emailing PAC about the issue. I do have the ir remote for the AVIC, so worse case I could convert to a PAC SWI-X but i'd have to deal with the hassle of mounting the remote eye etc. Plus sometimes in my X it doesn't work all that well in bright sun with the sunroof open.
Has anyone else experienced this or had any sort of issue or workaround? I am hesitant to pull the head unit out right now until I run RCA's remote turn on, but I guess I measure the difference in resistance of the buttons with the lights on and off.
Did some quick digging in the Electical Troubleshooting guide
OK Here's what I've come up with... The steering wheel illumination, and the audio control wiring resistor pack share a common ground. The steering wheel controller measures resistance relative to the controller's ground (head unit).
The only buttons that Don't work (or change when the wheel is lit / unlit) are the volume and memory + - buttons.
I did some quick digging and realized these are the buttons with lower resistance values.
What do you think about adding a 1k (or some value) resistor to the line and seeing if the lighting no longer affects the wheel controller.
Two options here the first pita one, is to ground either the lighting, or the audio resistor pack seperately.
Since its' not affected with the 1234 ohm Phone / Voice value and the 770 ohm Select value, i'm thinking that the led's add enough resistance to throw off the lower values, but are within tolerance for the higher ones. If we raise all the values, it may be within the threshold where they are still read by the controller regardless.
I'm hoping the audio controller will read a high enough value for this to work.