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Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 08, 2021 1:13 pm
by clarker63
Yes I think so.. (where has the delete post option gone..?).. see next response

Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 08, 2021 1:14 pm
by clarker63
Zulu4 wrote: Thu Apr 08, 2021 10:14 am Any thoughts on this idea?
Yes I think so... I'll caveat that with... as a mechanical engineer, circuits other than DC always confuse me ... WTF is a PWM signal? (yes I did google it at the time but other knowing what it stands for, I'm not sure how it works)! Sorry! :rofl:

Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 08, 2021 1:23 pm
by Zulu4
clarker63 wrote: Thu Apr 08, 2021 1:14 pm
Zulu4 wrote: Thu Apr 08, 2021 10:14 am Any thoughts on this idea?
Yes I think so... I'll caveat that with...
Thanks, that gives me a little bit of confidence. I'll have to get experimenting with a generic kit.
(Any electronics engineers out there that could shed some extra light ?)

Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 29, 2021 5:33 pm
by Kendodeal83
So got a whole loom have stripped out the heated seats wiring ready to fit this weekend it wasn’t to bad but this is the only option as I jus can’t buy a loom of the shelf

Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 29, 2021 6:10 pm
by ProfCJJ
Duplicate post - mods please delete if possible.

Z4 Heated Seat Wiring loom (Retro - Fit Kit)

Posted: Thu Apr 29, 2021 6:11 pm
by ProfCJJ
Zulu4 wrote: Thu Apr 08, 2021 1:23 pm
clarker63 wrote: Thu Apr 08, 2021 1:14 pm
Zulu4 wrote: Thu Apr 08, 2021 10:14 am Any thoughts on this idea?
Yes I think so... I'll caveat that with...
Thanks, that gives me a little bit of confidence. I'll have to get experimenting with a generic kit.
(Any electronics engineers out there that could shed some extra light ?)
I believe that a lot of aftermarket kits with more than one setting use PWM too - meaning that it should be a direct swap. I have yet to buy an aftermarket kit to prove this though.

PWM - or pulse width modulation is a way of simulating different analogue voltage levels through manipulation of a digital signal. The heated seat line is pulsed between 0V and 12V. For full power the pulse is almost always at 12V meaning that the average voltage level will be high. At the lowest setting the line will be pulsed so the line spends less time at 12V and more time at 0V. So by pulsing a line between 0V and 12V it’s possible to create an output at different voltage levels and thus different heating levels. It’s a bit of a “poor man’s” way of doing it though which is why it’s only done this way using the JB electronics module if you don’t have the full electric seats module - which needs a CAN bus connection.

HTH