[AGrainOfSalt]

Hello, I recently had an issue with my 118d where after pressure-washing my car,I get in and a whole bunch of notifications come up.The ignition is on,but the car won't start up(it doesn't even crank)/A couple of the issues on the screen were:
- Fuel supply malfunction - Full performance not available
- Traction control malfunction
- Tyre pressure sensor malfunction
etc.
windows,locking/unlocking,radio and stuff all worked fine

I managed to tow it to the service center from the wash and they suggested the battery being the culprit. They tried to start it up the following morning and it started up without any issue. All of the error codes they inspected(and there was a whole bunch of them,maybe 20+. were all related to low voltage). They changed the battery afterwards. The car drives perfectly fine now,but it did so before i had the issue as well..

Now from my logic, can the battery just decide to give enough voltage after one day to clear all of the issues? I am thinking this is not related to it. What do you guys think about this? Maybe the pressure washing part was a coincidence and this could have happened any time? Either way it was a pretty bad thing,considering I couldn't get the car in neutral as well...

[Windshieldfarmer]

Sounds like something got wet…. I’m assuming you weren’t pressure washing the engine bay but even an errant shot threw the front grill might have consequences if you have exposed connections. Just a thought.

[AGrainOfSalt]

It would make sense that something got wet according to my logic as well,but the thing is,the car has been washed thousands of times before,so this came as quite a weird thing.. it got me being afraid to wash my car.. Also,I wasnt’t washing,nor have i ever washed the engine bay.

[No one]

Originally Posted by AGrainOfSalt

Hello, I recently had an issue with my 118d where after pressure-washing my car,I get in and a whole bunch of notifications come up.The ignition is on,but the car won't start up(it doesn't even crank)/A couple of the issues on the screen were:
- Fuel supply malfunction - Full performance not available
- Traction control malfunction
- Tyre pressure sensor malfunction
etc.
windows,locking/unlocking,radio and stuff all worked fine

This resembles my recent issue.

Originally Posted by AGrainOfSalt

I managed to tow it to the service center from the wash and they suggested the battery being the culprit. They tried to start it up the following morning and it started up without any issue. All of the error codes they inspected(and there was a whole bunch of them,maybe 20+. were all related to low voltage). They changed the battery afterwards. The car drives perfectly fine now,but it did so before i had the issue as well..

They should've checked the battery rather than guess about it's condition (or did they and had it charged through the night?). Actually, when the battery is low you'll have a warning displayed.

[Windshieldfarmer]

Originally Posted by No one

They should've checked the battery rather than guess about it's condition (or did they and had it charged through the night?). Actually, when the battery is low you'll have a warning displayed.

Checking the grounding cable is a great suggestion.

[AGrainOfSalt]

I actually was scheduled to have the battery changed.They did notice a warning of sorts- an error code maybe(thats what they told me) when plugged in the obd port,but the car didn’t show any symptoms,nor did it have any dash warning lights come on. I was also told that this is no pressing issue,but I decided to change it as soon as possible anyways.. two days before the scheduled change and this happened.

The weirdest thing about it being the battery is that it doesn’t make sense to me if it drained suddenly to be able to start up just by sitting tight overnight??
Also,this happening right after the wash doesn’t seem like a coincidence to me.

I will have the starter ground cable checked,since i could not locate it and give an update.I also checked some wiring that I could see around the fusebox in the front,and apart from some small leaves,they seemed to be intact.

[Windshieldfarmer]

Originally Posted by AGrainOfSalt

I actually was scheduled to have the battery changed.They did notice a warning of sorts- an error code maybe(thats what they told me) when plugged in the obd port,but the car didn’t show any symptoms,nor did it have any dash warning lights come on. I was also told that this is no pressing issue,but I decided to change it as soon as possible anyways.. two days before the scheduled change and this happened.

The weirdest thing about it being the battery is that it doesn’t make sense to me if it drained suddenly to be able to start up just by sitting tight overnight??
Also,this happening right after the wash doesn’t seem like a coincidence to me.

I will have the starter ground cable checked,since i could not locate it and give an update.I also checked some wiring that I could see around the fusebox in the front,and apart from some small leaves,they seemed to be intact.

I helped jump start an older vehicle two days ago that was stuck, unable to start, in a parking lot. Turned out to be a loose ground cable to the battery. Car started easily once we tightened the cable.

[AGrainOfSalt]

UPDATE - went in at the service center to check the starter ground cable.The cable was fine.
Right as i was about to leave,the exact same thing happened - a bunch of malfunctions on the screen(dtc,tyre pressure monitor…)and the car wouldn’t start or crank.
It was a huge luck it happened there,since they connected through the obd port and the issue seemed to stem from the car not communicating with the DDE. The mechanic had an idea and replaced the dde relay on the spot.He noticed the old one was extremely hot to the touch(maybe this is relevant).The connections seemes fine as well.
Main thing is - the car seemed to occasionally lose connection to the dde.

After changing the relay,the car started with no malfunctions and he ran the scan for errors again,and there were none,so hopefully this was the issue.
Since this seems to have been happening every week or so,I wil report back in a short while if i have any issues again.