yesveeyem

I own Acura TL Type-S 2003 with 120,000 miles on it. Recently, I noticed that when the engine is ON, the passenger side headlight (low bean) gets on and the driver side light will be OFF. When I switch ON the headlight switch, the passenger side light will be ON and driver side light will still be OFF. Some times when the engine is ON, the lights on both sides will be OFF and gets ON when headlight switch is ON. Sometime the SRS, ABS, VSA lights on the panel gets on without any reason, and the mechanic could not find any issue with any of them. This whole issue happens inconsistently.
Fog lights on both side do not have this issue - they seems to be functioning normal.

I took this issue to mechanic and they replaced the right ballast ignitor and bulb. But this didn’t solve the issue and they finally said to me, they aren't able to identify the issue even after checking the entire wiring for 2 days.
will be great if I can get any advise on this from this thread

01tl4tl

simple fix actually- throw out the entire OE parts setup! not kidding!

you have ignitor/ballast failure = very common= see the 100 low beam threads on main list!
best bet is aftermarket- only 69 bucks at www.hidextra.com gets 2 new micro sized electronic waterproof ballast and ignitors with needed connector wires and 2 new quality bulbs
suggest bulb color 5000k for closest to stock

look for coupons online too, mention acurazine when you call ! they will hook you up and the shop can install in a hour- or diy!

do you have the dreaded moisture inside headlight lens after washing or rain?
that's what started the failure, it drips out a bottem drain and directly onto the ballast! ooops~
not to mention these systems are 15 years old in manufacture and design- technology advances alone are worth the replacement

01tl4tl

for your dash lights I would ck all the ground wires- there are several smaller ones from frame to engine/trans and the main battery ground cable
those crud up inside or the braided ones wear thru.
remove each wire and clean both ends and the place they contact with sandpaper or wire wheel/brush , test wire with multimeter for resistance

HOT water and Baking Soda in a cup- dip ends of battery cables in cup to dissolve crud growth
If there is crud growing on the outside of cables-battery terminals, pour that mix over them to nuetralize the acid- wash it away with clean water- do not touch any ugly stuff bare-handed!!
(general note for those new to diy electrical)

Once grounds are known good then take to any parts store for a free electrical test of battery and alternator
Often low battery will cause false codes/lights and poor running! is it more than 3 years old?
It wont hurt to start with the battery test!!
sitting at idle with lights on and ac on and weak battery = warning lights