How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Pete Your Own Question
Pete
Pete, Technician
Category: Australia Car
Satisfied Customers: 29139
Experience:  Over 17 years diagnosing and repairing various model vehicles with some certifications and training.
14928985
Type Your Australia Car Question Here...
Pete is online now
A new question is answered every 9 seconds

My ML270 built june 2004 is flashing the dash lights when

Customer Question

my ML270 built june 2004 is flashing the dash lights when switched off and the interior lights turn out, its like a disco in there!
JA: Have you checked the fuses? The dashboard bulbs?
Customer: ive found that the relay K12 (circuit 15) is pulsing
JA: What is the model of your '04 Mercedes?
Customer: ML270CDI
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: its a w163
JA: Anything else you want the mechanic to know before I connect you?
Customer: just looking to see if its something simple before i hand it over to an autoelec, my wife has noticed a leak in the sunroof , it could be water in the interior light circuit: ive taken down the lenses and it looks dry but thats only at bulb deep
Submitted: 2 months ago.
Category: Australia Car
Expert:  Pete replied 2 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

From what you have described here this sounds like a fault with one of the ecu control units causing this fault.I suspect one of the body control modules may be shorted out internally causing this fault.It may be one that has become wet from the sun roof leak as this can occur in some cases.The AAM ( all activity module ) in some cases can be the cause with it needing replaced but there are several other computers in your model that can cause this as well.

Unfortunately it does sound like it has to be looked into by an auto electrician/technician to read out any fault codes set and then those codes are diagnosed to then locate and repair the fault.They will have to do some electrical testing as well to help pinpoint the cause.Once the component is replaced depending on the component at fault it may have to be programmed by a dealer or auto electrician to work properly.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service,your 5 star rating is appreciated ( should be a link to click on here or above).You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 2 months ago.
thanks for your response, Pete.
i was hoping that someone out there would have seen this issue before and be able to be a little more specific with passed experience. Its kinda obvious that a chip somewhere is telling the relay to make and break but if it is a short then it would be reasonable to expect it to be a permanent fault rather then the intermittent pain that im experiencing - no? and why only when switched off not while running nor when the ignition is on and only after the interior light turns off? i could imagine a ic being sensitive to a volt drop but that would be more likely when a light turns on....
so i guess off to a sparkey with a merc scan tool $$$$ buggar
Expert:  Pete replied 2 months ago.

Your welcome

Unfortunately the codes do need to be read out/checked with an SDS machine to locate any codes set that may need diagnosed to pinpoint this issue.In some cases when no codes are set the SDS machine is used to monitor data signals to locate the faulty module or component.

But the AAM can fail or act up and can cause this fault here.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
have you done much work on the diesel MLs?
Expert:  Pete replied 2 months ago.

I have on some of these.I used to be a Mercedes dealer technician for 17 years.I am in the USA but they are all built pretty much the same since they all come from Europe.You will have to have this tested further to pinpoint which component is causing this fault here.Since there are so many electronics in this model ( like all Mercedes have) testing is the best way and a dealers sds machine is the best tool to help locate the fault.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
the Ml was built in Alabama
Expert:  Pete replied 2 months ago.

They are built in the USA but with German designs.The ML was at the time the only model built in the USA but this was all with the way Germany wanted them built so they are all set up the same way with the differences being left hand drive or right hand drive as well as different liter engines depending on what country it was being built for.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
sorry for the time delay but im in Australia
so do you know what the circuit 15 is?
Expert:  Pete replied 2 months ago.

No problem

Circuit 15 is when the key is on provides 12 volt power.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
power to what? each relay has a different job, i have to say your answers are remarkably general so far.
what do you know about critical terminal voltage on this car?
Expert:  Pete replied 2 months ago.

Unfortunately my diagrams are incomplete on this model here.I will open your question up for others to see if anyone else can help further.

I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.

Thanks Pete