So my left front Xenon low beam went out on my 2004 E500 4-Matic. Local mechanic installed a GE D2S bulb. It worked for three days, then quit. Finding myself in NYC with only one headlight, I stopped into Pep Boys. (I know, I know, but they're open late and don't require appointments and this is a light bulb for goodness' sake, and they actually do HID conversions, so it's not like they've never seen Xenon before.) I walk in, toting the pair of Phillips 5000K D2S bulbs that I had purchased in the meantime from a reputable supplier, being wary of knockoffs. Pep Boys said that the igniter was fried and suggested I use the OE part, so $200+ later at the dealer's parts window, I go back to Pep Boys with the new OE igniter and my set of bulbs, determined to finish this the same day. I want them to fix the left one and install the matched 5000K one on the right, so the new whiter light will come from both sides.

No problem, they're happy to do it. Thirty minutes later, they hand me my keys. I fire the car up, look at the lights, which look awesome, pull out onto the street, and the battery light comes on. I pull over, pull up the voltage on the dash display, and notice that it's 12 volts with the engine running. Yesterday, it was 14 with the engine idling. I pull back in traffic, and notice that the voltage goes DOWN from 12 as I accelerate. Ruh-roh! Four right turns later, I'm back at Pep Boys. Long story short, the battery is (of course) fine, but "there's nothing coming to the battery from the alternator to charge it". Oops, closing time, leave the car and call us tomorrow when the manager is here.

The alternator was giving me 14-ish volts on the dash indicator just yesterday, so obviously these guys did something to mess up my car.

One thing that did concern me as I was watching them through the waiting room window was that they put in the bulbs with the lights ON.

Maybe they will be able to quickly figure out what they did wrong, but would anybody knowledgeable in the forum have an idea of what they should check first? Although the Mercedes dealer is less than 5 minutes from Pep Boys, I would just as soon get it resolved quickly with-and-at Pep Boys, rather than having to open my bag of riches to have the dealer fix the problem and then fight Pep Boys over the bill.

EDIT: It occurs to me that Pep Boys was under the hood on two occasions. The first guy inspected the igniter and pronounced it fried, then gave me the car back so I could go get a new one. A different guy put in the new igniter and bulbs. He said the igniter just snapped into place and the bulb just went right in. Could the first guy who pronounced the igniter fried have disconnected something like the aux battery and not reconnected it when he gave the car back to me, and then the new guy didn't know to reconnect it? The second guy said that he himself didn't disconnect anything.

 

So helpful!!! Thanks!!!!

Let's review. Checked charging system Sunday. It was fine. Brought car to shop due to left lowbeam out. NO big red light on dash. Shop says needs electrical check. Accomplishes same. Only recommendation: need new igniter. Buy new igniter at dealer by driving car over there. No big red battery on dash. Return to shop. No big red battery on dash. New igniter and bulbs installed. BIG RED BATTERY ON DASH. System now not charging.

If I'm as much as a ***** as you suggest, pal, then I need to go buy a lottery ticket because lightning struck right when the car was at the shop. The alternator just happened to fail right then and there. Uh-huh.

Thanks so much for your kind help!!!!

 

You seem extra cranky lately. Did somebody eat your wheaties?

 

Was he ever NOT cranky?