[A1EK]

Hi All

My friends GL 320 has started to have an intermittent gear selection issue, I am looking for some help on!
It has been driving fine for. months, then recently he gets a red error on the dash to drive to work shop, he can move the shifter physically up and down from park to drive etc, however no gears can be selected? Sometimes it can happen when he is on the move, sometimes its when he first starts the car?
I have read that a low battery can can be a possible cause? He advised that the charging voltage is 13.7V this seems a little low perhaps?

Any advise would be great.

Thanks in advance.

 

[StenoPete1911]

Hi All

My friends GL 320 has started to have an intermittent gear selection issue, I am looking for some help on!
It has been driving fine for. months, then recently he gets a red error on the dash to drive to work shop, he can move the shifter physically up and down from park to drive etc, however no gears can be selected? Sometimes it can happen when he is on the move, sometimes its when he first starts the car?
I have read that a low battery can can be a possible cause? He advised that the charging voltage is 13.7V this seems a little low perhaps?

Any advise would be great.

Thanks in advance.

Hello. Get a new battery, for starters... And I believe it's your transmission solenoids and/or conductor plate.

This is a DIY job, however, if you're not too handy, have a local shop do it.

While you're there, change your transmission fluid also. GL.

 

[A1EK]

Thanks for the reply, think I will tell my friend to focus on the battery first, I take it, its the larger rear one?

 

[StenoPete1911]

Thanks for the reply, think I will tell my friend to focus on the battery first, I take it, its the larger rear one?

There are two... auxiliary and main. Both are next to the other and are underneath the passenger seat...GL.

 

[wallyp]

The small gel-cell battery is the back-up battery for shifter operation - that would be my first suspect. Those are just standard alarm system/lantern/riding toy batteries, and are available quite cheaply on-line. Buy by the number on the side of the battery.

 

[A1EK]

The small gel-cell battery is the back-up battery for shifter operation - that would be my first suspect. Those are just standard alarm system/lantern/riding toy batteries, and are available quite cheaply on-line. Buy by the number on the side of the battery.

Hi Wallyp

Good to know, is the small battery like this one in the link?

Mercedes-Benz ML R GL - Auxiliary Battery Replacement

We hope you find the Mercedes-Benz ML R GL - Auxiliary Battery Replacement guide helpful. Check these troubleshooting and repair guides for more help on your

www.youcanic.com

 

[wallyp]

Yes. I really don't know if the small back-up battery will cause your problem.

 

[StenoPete1911]

Yes. I really don't know if the small back-up battery will cause your problem.

Yes, it will. The aux battery is only for gear selection "IF" the main battery is faulty/undercharged/dead.

Also, at the same time, if the main battery is faulty/underchanged/dead it will give of random cell errors, as the system is made to run at a certain voltage. Anything beyond those tolerances will give cell errors.

You want to make sure you change both batteries at the same time. GL.

 

[Handsofstone]

I just went through this on my 2011 GL450. New car to me and have only had less than a month. I started getting random messages about Pre Safe warnings and also SRS malfunction and researched on this forum. Once started and I would get the message it wouldn't let me shift into gear, so I was concerned and then after I kept trying it finally would go into gear and the messages would go away. Not being super familiar with the car yet I actually called a dealer for an appointment and that would have taken 3 weeks and she says kind of half heartedly......Usually a Battery issue, so that was all I needed to hear. I got what I thought was both battery's, the main one and the auxiliary. Once involved in the changeover i figured out the new auxiliary battery was the wrong battery. I pulled the auxiliary battery out and tested it and it was ever bit of 12.8 volts or fully charged. The auxiliary battery went back in and the new main battery went in. Out of curiosity I put the main battery on a trickle charger all night and it still wasn't holding a decent voltage at about 12.45 volts. Since the change....."Knock on Wood" I haven't had any issues with the error messages since the 2017 year dated battery was changed!!

 

[StenoPete1911]

I just went through this on my 2011 GL450. New car to me and have only had less than a month. I started getting random messages about Pre Safe warnings and also SRS malfunction and researched on this forum. Once started and I would get the message it wouldn't let me shift into gear, so I was concerned and then after I kept trying it finally would go into gear and the messages would go away. Not being super familiar with the car yet I actually called a dealer for an appointment and that would have taken 3 weeks and she says kind of half heartedly......Usually a Battery issue, so that was all I needed to hear. I got what I thought was both battery's, the main one and the auxiliary. Once involved in the changeover i figured out the new auxiliary battery was the wrong battery. I pulled the auxiliary battery out and tested it and it was ever bit of 12.8 volts or fully charged. The auxiliary battery went back in and the new main battery went in. Out of curiosity I put the main battery on a trickle charger all night and it still wasn't holding a decent voltage at about 12.45 volts. Since the change....."Knock on Wood" I haven't had any issues with the error messages since the 2017 year dated battery was changed!!

Hello. Sounds good. Keep knocking and driving, about 10 years later, your battery should still be functioning. 🤣 🍺 GL.

 

[Witek_M]

Here is how GL450 looks with both dead batteries.

 

[Handsofstone]

Here is how GL450 looks with both dead batteries.

Should we call that......"UGLY"!!!!!

 

[Handsofstone]

Hello. Sounds good. Keep knocking and driving, about 10 years later, your battery should still be functioning. 🤣 🍺 GL.

To report back on the Pre Safe Issue and SRS Issue after the main battery was replaced. I drove to Florida and back about 2400 Miles total including while I was there and after I got there I started the car up and got the same issue with the Pre Safe warning etc. It stopped me briefly from shifting into gear, but that was it and I haven't seen it again.??????

 

[StenoPete1911]

To report back on the Pre Safe Issue and SRS Issue after the main battery was replaced. I drove to Florida and back about 2400 Miles total including while I was there and after I got there I started the car up and got the same issue with the Pre Safe warning etc. It stopped me briefly from shifting into gear, but that was it and I haven't seen it again.??????

Hello. If you drove 2400 miles and it occurred once then I'd have to go with a faulty sensor or blocked sensor. I'd rule out a bad module since you drove 2400 miles.

Find the sensors that are in the front bumper and clean them. GL.

 

[Handsofstone]

Hello. If you drove 2400 miles and it occurred once then I'd have to go with a faulty sensor or blocked sensor. I'd rule out a bad module since you drove 2400 miles.

Find the sensors that are in the front bumper and clean them. GL.

Pete, What would the sensors have to do with the truck shifting out of park into gear? Those sensors are mainly parking sensors to let you know how close you are to objects and also similar to the lane assist sensors on the sides. I cant see how they would be tied into the gear selector? I am of course not as familiar with these trucks as you and others are on this forum......but am becoming more and more familiar as time goes by!!!!! Just replaced a blown Parking / marker light after my trip. The little tiny bulb on the headlight assembly that is clear and closer to the middle of the car. My hands are too fat!!!!!

 

[jrziggy]

Hi all. I'm in the same boat with all the crazy errors including the one to not allow shifting gears. It did it once, then no issues for several weeks. Suddenly it's consistently happening. I've checked where the central gateway controller lives under the driver's seat and there's no water there or in the battery compartment. All the fuses are good. I haven't replaced the batteries yet because they were newly installed in January of 2020. Can a legit-quality 2 year old battery be bad? @Handsofstone - did you resolve your issue, and if so, how? Thanks. Side note - I too have tried to jam my chunky hands in that small space to replace those bulbs. lol