Apologies for this lengthy post.
Right, bought a towbar for my BMW E60, grand job fits well, no complaints.
Bought this bypass relay for the wiring;
https://www.amazon.co.uk/gp/product/B01MFDI2CM/ref=ox_sc_act_title_1?smid=AGP7DNYDAXCIB&psc=1
Fitted as per instructions. All works bar the sidelights.
Allegedly, since the E60 has a shared brake/ tail light I don't need to tap into the sidelights and that the relay should sense the shared brake/ tail and supply current to the sidelights....in theory.
In practise it ain't working.
If I tap into sidelights and wire them to the relay they also don't work that way.
I believe BMWs are renowned for being a bit of a ****** in this regard. They have a pulsed signal system and I believe it is preventing the relay from "seeing" the low voltage (around 3v) signal from the brake/ tail wire. Alternatively i may have a faulty bypass relay
To get around this i have rigged up a standard 4pin 12v 25amp relay with a 15amp fused connection direct to the battery. It has an earth taken to the cars standard earthing point, a signal feed from the sidelight wiring and then the output feed to the trailer plug.
It works.....however, due to this pulsing voltage that BMW employ, the wee relay is clicking as it constantly opens and closes!
I assume this isn't normal, nor healthy for the relay?
Could I add a capacitor from the sidelight feed wire and the relay to "smooth" out the pulsed signal?
Thanks in advance!
Anton
Right, bought a towbar for my BMW E60, grand job fits well, no complaints.
Bought this bypass relay for the wiring;
https://www.amazon.co.uk/gp/product/B01MFDI2CM/ref=ox_sc_act_title_1?smid=AGP7DNYDAXCIB&psc=1
Fitted as per instructions. All works bar the sidelights.
Allegedly, since the E60 has a shared brake/ tail light I don't need to tap into the sidelights and that the relay should sense the shared brake/ tail and supply current to the sidelights....in theory.
In practise it ain't working.
If I tap into sidelights and wire them to the relay they also don't work that way.
I believe BMWs are renowned for being a bit of a ****** in this regard. They have a pulsed signal system and I believe it is preventing the relay from "seeing" the low voltage (around 3v) signal from the brake/ tail wire. Alternatively i may have a faulty bypass relay
To get around this i have rigged up a standard 4pin 12v 25amp relay with a 15amp fused connection direct to the battery. It has an earth taken to the cars standard earthing point, a signal feed from the sidelight wiring and then the output feed to the trailer plug.
It works.....however, due to this pulsing voltage that BMW employ, the wee relay is clicking as it constantly opens and closes!
I assume this isn't normal, nor healthy for the relay?
Could I add a capacitor from the sidelight feed wire and the relay to "smooth" out the pulsed signal?
Thanks in advance!
Anton
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