Mbsjones

Need help please! I bought a pre-owned MB 10 days ago. Within a day, the electrical consumables would all die moments after shutting off the car to where my keyless entry did not even work. Only after starting the car would power be restored, but then the dreaded Check Engine Light came on.

After doing some research, I determined my consumables auxiliary battery in the trunk was fautly. After taking to dealership, they ran a diagnostics and confirmed it was just the battery. They also said the check engine light was attributed to the system not getting enough power from the faulty battery. Whew! (so I thought)

$420 and a new battery later, I drove the car home. No sooner than I turned off the ignition, and just turned the electrical consumables back on, the car died again in 2 mins. 10 mins later the Check Engine Light came on again.

This car was bought with no extended warranty with 28K miles on it. The Lexus dealer from which I bought this car hasn't responded to any emails or phone calls the past week. I'm bracing myself for the fact I bought a lemon, and there is a major electrical problem in this car, but if anyone has any other suggestions, please let me know.

I have attached some pics of the dash error messages right before the electrical consumables die. Thanks in advance for any assistance.

marthyh

1st Check all fuses are ok with fusemap that lives in the toolset at the sparewheel-compartiment.
Hope there is one or more blown fuses..

2nd Have a descent drive for 1hr or so to charge both batteries

3rd Good Luck!!

jbondox

2 things to check,

drop the under dash and look to see if anything aftermarket was installed. it seems it is an eis issue or gateway issue

the other thing is to pull the comand and check to see if anything behind it was modified.

if there is a gateway problem between the comand and cluster, the dash will xmas tree like that.

the yellow wires, under the dash going to the can distribution is for the cluster

Mbsjones

Thanks for the replies. Will check all of those things and keep my fingers crossed. Will report back with my findings.

percykwong

Also check the condition of the harnesses / wiring / connectors.. If they're hosed or look bad, let me know.. I used to build harnesses for a while (I can set you up with a new harness for much cheaper). Electrical issues are almost always a connection problem.

You might also want to check the alternator.

percykwong

Also check the condition of the harnesses / wiring / connectors.. If they're hosed or look bad, let me know..

I used to build harnesses for a while (I can set you up with a new harness for much cheaper). Electrical issues are almost always a connection problem.

You might also want to check the alternator. I've seen a bad alternator do some interesting stuff to batteries.

Once you get the car running, I would definitely look into an extended warranty. Even a one year warranty would be fine. It'll help you get through the rough patches as you're shaking your new ride out.

Cheers.

-Percy

Mbsjones

Thanks Percy. I am taking to dealership tomorrow to get all of this checked out. Does sound like bad wiring though. Will keep you posted. Thanks again.

token

Just curious, what was the problem?

Mike5215

Looks like a basic under volt situation. ABC and ESP rely on the main battery I think, Did they also check the starting battery and alternator output? May be a simple fix. Is MB doing the work or the Lexus store?

Hekkie Smith

Percy,
hi
My w221 2007 wont start, I tried to jump-start it and it went well but yesterday I wrongly connected the cables, I noticed the fuse (20A) was blown up, I had I new one and connected the car in the way then i tried to start it again and it kept blowing up the fuse again and again,-NOW IT WONT START-
any help please
the front sam has been checked it works fine.