Mercedes-Benz key specialist · Atlanta, GA
Mercedes-Benz EIS and Ignition Repair in Atlanta
If the key goes in but won't turn, the dash stays dark or the steering won't unlock, your Mercedes may have an EIS problem. Mercedes Key Programming diagnoses it at your car in Atlanta and tells you the fix and the price before any work.
Signs your EIS is failing
The EIS (electronic ignition switch) is the slot your key goes into. It reads the key and tells the car it's allowed to start. When it fails, you usually see one of these:
- Your key goes in but won't turn.
- Nothing happens on the dashboard when you insert the key.
- Steering stays locked, sometimes with a clicking or whirring sound from the column.
- Your car starts on some days and not on others.
- Key gets stuck in the slot and won't come out.
- One key works and the other doesn't. That one usually points to the key, not the switch.
Those symptoms overlap with a dead key or a failing steering lock (ELV), so guessing gets expensive. We test the key first, then the switch, then the lock. Have a spare? Bring it out when we arrive, since a second key makes the test faster. If it turns out to be the key, our key fob page covers what comes next.
On the W204 C-Class, W207 E-Class coupe and W212 E-Class, the steering lock (ELV) fails often, and a new key won't fix it: the lock gets repaired or replaced on its own. With FBS3 cars (about 2003 to 2014) we can also read, back up, repair or replace the EIS itself, the same day.
FBS4 cars, most from about 2015 on, are handled differently: a key problem gets a factory key we order for your VIN through NASTF, which takes longer. Switch repairs on those we confirm by VIN first. Unsure which one you drive? Check your model and year.
EIS FAQ
What is the EIS on a Mercedes?
It's the electronic ignition switch: the slot where you insert the key. The EIS reads the key and lets the car start. When it fails, the key may not turn, or the car may act like it doesn't recognize the key at all.
How do I know if it's the key or the EIS?
Testing tells, and a second key makes it quick. If your spare works and the first key doesn't, the key is the likely problem. When neither key works, the switch or the steering lock moves to the top of the list. We check both at your car.
Can a Mercedes EIS problem be fixed without the dealer?
Often, yes, on FBS3 cars (most models from about 2003 to 2014). Where the car is parked, we can read, back up, repair or replace the EIS, and you get the options and the price before we touch anything. On FBS4 cars, most from about 2015 on, call with your VIN: if the key is the problem, we order a factory key and bring it to you.
My key won't turn in the ignition. What should I try first?
Try your spare key, and gently turn the steering wheel left and right while you turn the key. If neither helps, don't force it: a bent or stuck key makes things worse. Call (470) 229-2853 and tell us what the dash does when the key is in.
Do you need to tow my Mercedes for EIS work?
In most cases, no. We come to the car anywhere in our Atlanta service area and diagnose it there. If the fix needs the car moved, you'll know before you pay for anything. Lost the key as well? See our lost Mercedes key service.
Will a new key fix a steering lock that won't release?
No. On the W204 C-Class and the W207 and W212 E-Class, a failing steering lock (ELV) is common, and a new key won't fix it. The lock has to be repaired or replaced on its own, so we test it before we quote anything.
Does a new EIS mean I need new keys too?
Usually the keys have to be matched to a new or replacement switch, because the switch and the keys talk to each other. We explain what your car needs, keys included, in the price we quote before the job starts.
Key won't turn?
Call (470) 229-2853Keep reading
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