Turn Off the ESP/BAS Warning Light

The amber ESP/BAS warning on your 300’s cluster is almost always harmless when it appears right after a battery change or a brake job. This big rear-drive Chrysler steers its stability program off a steering angle sensor that forgets where straight-ahead is the moment power is cut, and the lamp usually lights a handful of drives later. A two-minute driveway relearn brings it back — no dealer visit or scan tool. Do it on flat ground with the wheels straight.

How you know it’s just a lost calibration

The tell is timing: the light was absent, you disconnected the battery (or a shop touched the ABS, wheel bearings or a brake sensor), and about five ignition cycles later the ESP/BAS lamp is on steady with no change in how the car drives. On the 300 it typically comes paired with a lit BAS symbol, and the stability system quietly stops intervening. If instead the light flickers on and off while cornering, or arrived out of the blue with no recent work, treat that as a real fault rather than a lost reference.

Before you start: park on level ground with the engine idling, keep your foot on the brake, and make sure no one is standing near the front wheels — the power steering swings the wheel quickly and firmly from lock to lock.

1. Start the engine and let it idle. Keep the car stationary throughout.
2. With the road wheels pointing straight ahead, centre the steering wheel.
3. Turn the steering wheel all the way to the left until it reaches the internal stop, then all the way to the right until it reaches the opposite stop.
4. Return the steering wheel to the centre, straight-ahead position.
5. Switch the engine off, then restart. The ESP/BAS light should now be out.

Why it happens

Electronic Stability Program compares where you are pointing the wheel against how the car is actually rotating, so it needs an exact zero for straight-ahead. That zero is stored electronically, and a battery disconnect erases it. Until the sensor is taught centre again, the module refuses to trust its own steering input and lights the lamp instead of risking a wrong brake intervention.

If it doesn’t work or the light comes back

• Make sure the front wheels are genuinely straight before you start — the routine records whatever it sees as centre, so a crooked start miscalibrates it.
• Turn all the way to each internal stop. A partial swing on a heavy 300 is the most common reason the relearn silently fails; you should feel the rack hit its hard stop both ways.
• If the lamp returns within a few drives with a known-good battery, suspect a real chassis fault — a lazy wheel-speed sensor or the angle sensor itself — not a lost setting. Read the stored ABS/ESP “C” codes at autodtcs.com to see which corner is complaining.
• An SRT8 uses larger Brembo brakes but the same sensor and the same procedure — there is no performance-model variation here.

Work on level ground with the park brake set and clear of traffic, and rerun this calibration every time you disconnect and reconnect the battery on your 300.