W124/W201 ignition lock defective? Check & replace the steering lock
Short answer: If the ignition key on a Mercedes W124 or W201 no longer turns, spins freely, or the steering stays locked, it's almost always the steering lock that needs replacing – the worn lock cylinder or the ignition/starter switch behind it. Solution: replace it with a tested genuine steering lock, part number A1244622030, with a matching key for 219,00 € (gasoline models with manual transmission).
It starts harmlessly: in the morning the key goes into the lock a bit stiffer, you wiggle it briefly, the car starts. Six months later it won't move a millimeter anymore – or it spins freely without the ignition responding at all. On the 190 and the 124, those are the classic end points of a worn steering lock. This guide shows how to narrow down the fault and which genuine part fits.
Genuine steering lock for W201 and W124: die-cast housing with lock cylinder, locking bolt and round ignition/starter switch – tested, with key.
Symptoms
| Symptom | Likely cause |
|---|---|
| Key only turns with force, or not at all | Worn tumblers or resinified lubricant in the lock cylinder |
| Key spins freely, ignition stays dead | Connection between the lock cylinder and the ignition/starter switch broken |
| Ignition and warning lights come on, the starter doesn't turn | Worn contact for terminal 50 in the round ignition/starter switch |
| Steering stays locked even though the key turns | Jammed locking bolt in the steering lock housing |
| Ignition and starter normal, only the doors can no longer be unlocked | Not the ignition lock: then the door lock cylinders or central locking are the cause – see W124 door lock defective |
| Key turns cleanly, starter cranks strongly, engine doesn't start | Not the ignition lock: check the injection system's power supply first – see Overvoltage protection relay defective |
Causes
The steering lock of the 201 and 124 model series combines two components in one die-cast housing that age differently. At the front sits the lock cylinder with spring-loaded tumblers, behind it the locking bolt, which extends when the key is removed and locks the steering spindle. Bolted to the rear end is the round ignition/starter switch – terminal 30 (permanent positive), 15 (ignition) and 50 (starter) all run through it.
After decades and tens of thousands of lock cycles, the tumblers and the key bit have worn down, springs fatigue, and old oil resinifies into a dust-binding layer. Penetrating oil then only postpones the problem by a few months. At the same time, the ignition/starter switch is working at its limit: the starter control circuit runs through its contacts, and every start causes a little contact burn. Eventually it stops switching through cleanly – the ignition comes on, but the starter stays silent.
Testing it yourself
- Test the spare key – If the lock runs noticeably better with the rarely used spare key, it's mainly your everyday key that's worn. If it stays equally stiff, the problem is the cylinder.
- Relieve the steering wheel – Gently move the steering wheel back and forth while turning the key. If it then works, only the locking bolt is jammed under preload – a common false alarm when the wheels are turned.
- Separate the mechanics from the electrics – If the key turns cleanly through all positions, the fault is in the electrical part. If it catches or jams, it's the other way around.
- Measure terminals 15 and 50 – If the warning lights come on at "ignition on", terminal 15 is fine. In the start position, use a multimeter to check whether voltage reaches the control cable to the starter. If it's missing, the ignition/starter switch is no longer switching through.
- Check the connector and contact pins – Under the steering column trim, disconnect the round connector and the small auxiliary connector: bent, tarnished or scorched pins explain intermittent faults that would otherwise be blamed on the lock.
Solution
A worn-out lock cylinder cannot be readjusted, and a burnt ignition/starter switch cannot reasonably be repaired on the vehicle. The clean solution is replacement with a tested genuine part: Ignition lock / steering lock, part number A1244622030, for 219,00 € each. On our units, the included key turns cleanly through all positions, the mechanism latches correctly, the ignition/starter switch is fitted, the contact pins are straight, and the two-pin auxiliary contact with cable and connector is present. The housing shows a patina of age, no cracks.
Three points before installation: the lock has a keying of its own – the included key doesn't open the doors, glovebox or trunk lid; anyone who wants a uniform keying swaps in the cylinder from the old part. It is the version for gasoline models with manual transmission. And since the W201 and W124 had different wiring harnesses over the production run, compare the ignition/starter switch and auxiliary connector against your old part using the product photos. The lock is fitted on the steering column tube under the steering column trim. More genuine parts: category W201 and W124.
The round ignition/starter switch at the rear end of the housing – straight, clean contact pins are essential for reliable starting.
The matching replacement part – buy it directly from us
Mercedes ignition lock steering lock W201 W124 gasoline models, with key
Part number A1244622030 · Genuine Mercedes-Benz · tested, with key
219,00 €
Compatible vehicles
The table below shows the compatibility list for this lock – gasoline models with manual transmission:
| Model series | Body style | Models (selection) | Production period per type list |
|---|---|---|---|
| W201 (190) | Sedan | 190 (201.022), 190 E 1.8 / 2.0 / 2.3 / 2.6 (201.018 / .024 / .028 / .029), 190 E 2.3-16 and 2.5-16 (201.034 / .035) | 1982–1993 |
| W124 | Sedan | 200, 200 E, 230 E, 260 E, 280 E, 300 E, 320 E | 1984–1995 |
| S124 | T-model (estate) | incl. 230 TE, 300 TE | 1984–1995 |
| C124 / A124 | Coupe / Cabriolet | incl. 300 CE | 1984–1995 |
Does not fit: W116, W123, W126 (different steering lock design), W202, W210, W140 and all model series with an electronic immobilizer, as well as diesels and automatics. Not sure? Send the chassis number and model year via the contact form send it to us – we'll check for free.
FAQ
Does the steering lock also fit diesel or automatic vehicles?
No. This is the version for gasoline models with manual transmission. Diesels need the variant with a mount for the vacuum shut-off, automatics the one with a linkage for the key-removal lock. Compare the housing shape and connector layout against your old part before buying.
Can I keep using my current car key?
Not without modification. The lock has its own keying; the included key doesn't open the doors, glovebox or trunk lid. Anyone who wants a uniform keying swaps in the cylinder from the old part.
How do I tell whether the lock cylinder or the ignition/starter switch is defective?
If the key catches or jams, the lock cylinder is worn. If it turns cleanly through all positions without the ignition or starter responding, the fault is in the round ignition/starter switch (terminals 30, 15, 50).
Does the lock also fit the W123, W126 or W202?
No. W116, W123 and W126 have a different steering lock design; W202, W210, W140 and all model series with an electronic immobilizer are excluded as well. It covers W201 and the 124 model series.
How much does the steering lock cost and is it available immediately?
The tested genuine steering lock A1244622030 costs 219,00 Euro each and is in stock in several units – each one with its own keying and matching key.
More reading: W124 door lock defective? Symptoms, testing and solution – the right diagnosis if it's not the ignition lock but the door lock cylinders that are jamming.
KFZTeile-Thot is a specialist workshop for tested and refurbished Mercedes parts with our own test benches and over 1,000 eBay reviews (almost all positive). We have ignition locks, lock cylinders and many more genuine parts for the W201 and W124 tested and in stock. Questions about fitment? Call us: 0179 8991069 (Mon–Fri 8 am–6 pm) – or use our contact form.