View Full Version : Fitted HIDs to all my lights
Burgundy8
7th February 2014, 12:38 PM
and ended up with the usual problem of a massive dip in power when the lights are first turned on. Usually it cut all electrics for a couple seconds and then everything powers back up fine, now I understand what is happening and my installer tried adding cancelers which did not work, then he tried running power directly from the battery but for some reason that didn't work either.
My question is....what is the long term effect, if any on the Becm, if I let it stay as is.
Mike
benji
7th February 2014, 06:50 PM
I've read of two other p38's with HID on the driving lights, that have drawn the main power supply for the Ballast resistors through the BECM. Both worked for a while, and then they stopped working.
My understanding is that the Ballast resistors have a very high unrush current, that (IMO) is to much in the long term for the FET relays inthe BECM. Looking up the part numbers of these relays a few years ago they don't have a very high current rating at all.
If your auto elec. triggered the ballast resistors through a relay from the battery then I can't imagine there'd any effect on any of the cars electrics (unless you've a bad battery / earths etc...)
I was looking at putting HID on the driving lights only; but when hearing that someone on this forum had trouble in the same way that i'd heard of before on rangerovers.net i decided against it.
Hope this helps.
wayneg
7th February 2014, 08:02 PM
I have had hids for a few years with no issues apart from the power drop on initial start-up. As there are now Cob LED H4 bulbs available ( as fitted with good results by others) I think it wise to go that route for any new installs.
I will be fitting them to the new car
davidsonsm
7th February 2014, 09:20 PM
I second these opinions. I'll be swapping my hid's out for led's, given I believe I've burnt out two becm relays - now my lhs dipped beam and rhs main beam don't work. I've ordered replacement relays. Just got to fit them at some point.
Hoges
7th February 2014, 11:18 PM
is this just a bulb swap or do you take account of reflector design as well in determining an appropriate substitute...?:angel::wasntme:
Scouse
8th February 2014, 11:46 AM
I've had 50w HIDs fitted to all 4 lights now for around 6 years. No start up issues, no BECM issues, no bulb fail issues.
I'll be fitting the same spec globes to the diesel when it goes on the road.
Hoges
8th February 2014, 12:14 PM
therein seems to be the problem: higher wattage may not necessarily be better.. indeed you could say "...you need to know what's watt...ey what?" :eek: :angel: :wasntme:
rc42
10th February 2014, 08:48 AM
I've used 110/90W H4 bulbs in the past with no BECM issues or the alarming power dropout to the entire dash so I don't think the HID issue is nominal load current related but it does seem to be surge related.
I took all of the HIDs off my P38, the H4s are now the new dual Cree units which give good enough light (better than standard bulbs although not in HID territory), the aux driving lights have standard bulbs with the whitest output available (although not the brightest) as I wanted to try to minimise the colour difference between them and the LEDs.
An 80 LED light bar takes care of the real main beam lighting power, not so useful around town though unless you don't mind being blinded by every road sign.
Another consideration is that no H4 HID bulb is type approved for the P38 headlamp assembly so they are illegal in all states and you could get fined for using them. Never stopped me though but do try to minimise the dazzle for other road users.
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