The initial quick flash of light is apparently normal for these types of=20 lights. All else works fine. However, when I was getting all the=20 circuits figured out, I remember that the HIDs did not work with=20 alligator-jumper wires as temporary wiring. Doubling up on some of=20 these solved the issue. And I had tested the jumpers to ensure they=20 were good, so it was really a matter of wires being too small. This=20 does indeed point me to running separate wiring. I'm not thrilled with the existing wire paths anyway. Battery in trunk=20 on passenger side. Positive runs across trunk then up the driver's side=20 through the firewall and to the starter solenoid on the driver's side=20 inner fender apron. From there the positive splits to the headlights=20 and also back to the firewall across the other side and down to the ECU=20 & ignition amp on the passenger front footwell. I've been concerned=20 about the wires gauges used for some of this, so thinking I should route=20 wires directly from the battery to the ECU & ignition amp, but yes, I=20 agree that I should do that for the headlights also. Cheers, -Neil. On 2/17/2015 2:40 AM, Perry Curling-Hope wrote: > Expanding upon what Richard said, ( poor ground path somewhere) disconnec= t > the HID headlamps from the wiring, and power them directly from a battery > with cable. > > If they behave normally, as expected, the 'surge' is not being caused by > them. > > Does the car then behave normally minus the headlamps? > > Probe around with a multimeter in the headlamp sockets for voltages and > resistances relative to chassis to find the dodgy connection(s) > On 17 Feb 2015 08:00, "Neil" wrote: >> Recently got and old car roadworthy and it has HID headlights in it. >> The bulbs have an interesting behaviour in that when first turned on, >> they emit a quick flash of light, then instantly dim, and slowly >> brighten back up to operating brightness. What's not good is that every >> so often, that initial flash causes enough of a power surge to knock out >> the ECU ( >> http://www.wmsracing.com/wmsweb/SDS-WMS-SDS-Digital-Injection-System.htm= l > ). >> Or perhaps it's knocking out the aftermarket ignition system ( >> http://www.jegs.com/i/MSD/121/62152/10002/-1 ), as after the surge, the >> ECU shows "RPM error". I'm planning on adding some type of filter to >> the ECU or ignition module power lines (no prob with that), but >> wondering why I shouldn't try to reduce the surge instead. >> >> How would I go about doing this? The HID lights have the bulbs, a relay >> module and a couple ballasts. Would there be a simple way to reduce the >> surge for bulbs like this? Or would doing so impede the bulbs operation= ? >> >> Cheers, >> -Neil >> >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .