Matt S.

I have the Airmatic Malfunction. Dealer calibrated ride height. After sitting overnight the front right was low again. Dealer checked the system, no leaks or errors, and recalibrated ride height. Same thing 2 days later. Values entered into calibration are not saving although it appears they are,

Right low beam only comes on with "automatic" setting, when starting the truck. If I go into a tunnel and the lights come on, only the left low beam lights, and "Check RIght Low Beam" comes up.

Automatic wipers are erradic. Heavy rain, slow wipers. Light rain, fast wipers.

Indy says the voltage to the front right ride height sensor and the front right headlight harness are both around 9V, not 12V.

He thinks the front SAM controls all of these things, and has gone bad. I'd like to feel like this is the problem before replacing the SAM.

Opinions?

Thanks

cadetdrivr

This platform, like most new MBs, is extremely sensitive to battery issues and can demonstrate all sorts of wacky issues with marginal batteries.

Have you checked both the MAIN and AUX batteries as part of your troubleshooting?

chassis

Agree. If the batteries are original, replace both of them on principal, based on age. Then start diagnosing the headlamp and airmatic systems.

Matt S.

batteries are about a year old. Calibrated AIRmatic once again, looked good. Next morning front right is down 20mm and the malfunction screen is on. Checked calibration and values and the car defaulted back to pre-calibration numbers. Control module issue? Compressor and valve block were changed when the issue began. No leaks anywhere. Only code is “perform AIRmatic calibration”.

chassis

Seems like a full and deep diagnosis is needed.

- What is the history of this vehicle?
- How long have you owned the vehicle?
- How many miles are on the vehicle?
- What work have you recently done, or had done, that has not yet been described above?
- What codes have you read?
- Do you have WIS, EPC and Xentry/DAS? This assumes you DIY your own repairs.

In summary: start with electric and electronic diagnosis. This requires the proper tools and software. This will lead to to hardware/component replacement, should it be necessary.

The air suspension is a finicky and complex beast and it needs to be treated as such.

mcoady1

My x164 had a bunch of weird things happen related to front SAM and it ended up being water soaking the SAM from a shoddy windshield job by previous owner. My understanding is it's one of the lowest parts of the car on passenger side so water will accumulate there if it is getting in from a door, windshield, plugged drain etc. Water will cause weird issues; mine had parking lights staying on only on one side, constant airmatic valve block clicking (drained battery), and right before insurance totaled it the outdoor temperature reading was 117 F or something like that.(yes that's right - insurance wiped their hands clean of an otherwise immaculate x164 since it was water damage, so be careful when contacting insurance if it is water). Likely a few other weird symptoms I can't recall.

I'd peek in the SAM compartment to make sure there's no signs of water. I'm pretty sure x164 and x166 have similar SAM setups but am not positive, so may want to fact check me here in case it's completely different. I fortunately have not had to mess with my x166's SAM!

Panzerknacker

I’m necroposting here but if anybody has a photo or how to access the front SAM (X166) then that would be nice.