Will a "bad" ETA damage modules? ('94 E420)
 

Hello everybody!

As some of you might have seen, my E420 is having "issues". Yesterday I was informed that I should get a new LH module and a Base module. I was also advised that the ETA was going, and that I ought to get a new one.

Since the ETA uses the same half-ashed wiring that the harness used (replace it), is there a chance that a bad/going bad ETA can damage the aforementioned modules?

If so, then I would get a rebuilt ETA, or else I'd just be throwing good money away, and hunt for parts again.

Thanks!

-Larry

Larry,

If the ETA is bad it just will not work. No such thing as going bad, either it does work or don't work properly. I have heard that ETA can take out other electrical items but only in the case of faulty or crack wires. Issues such as bad wiring harness could cause other electrical components to be harmed. It is possible to have a fuse blown first before you have a major electrical component harmed by the ETA. Most likely if your ETA is bad it is because of the worn gears inside the ETA if you don't have a electrical harness issue.

One way to confirm whether or not your ETA is working is to turn your ignition switch to the #2 position as if you are scanning codes. Then listen for the ETA to make a hi-pitch noise. The hi-pitch noise is the ETA's butterfly setting itself in the correct position to allow the engine to start with proper airflow. Look inside the ETA and see if the butterfly is adjusting itself by opening and closing.

If you don't hear the hi-pitch sound or see the butterfly adjusting itself then you may want to reset/reprogram the ETA. I can't remember at the moment how to reset the ETA but I will get back to you after I look it up. It goes something like turn your ignition switch on and stepping on the accelerator pedal but I will get back to you on that one.

Far as the Base Module, I rarely here of it going bad. Usually a fuse would blow I really doubt if your Base Module is fried. I continue to suggest that you scan each module to see if you get fault codes before buying a new modules.


JimF can really help you out on ETA I suggest contacting him. I had my fair share of dealing with ETA so before you purchase a new one make sure yours is definitely shot.

the modules installed in an MB has proven to be a very reliable part that does not break easily, only when abused, what seems to be the problem of your car for you to decide to change the modules and the ETA (what made you come to the conclusion that these parts are bad? may I be of help? offshore mercedes benz dealership

Larry, with 160K on the '94 E420, the first that comes to me, is was the wiring harness replaced?? If not, I'd certainly start there. As you have read here, many cars where brought back from their apparent 'death' when it was replaced.

I've NEVER seen one of the modules go bad . . . and in time (12 years), my tech has maybe replaced one???? The DTCs that are generated point to a faulty EA but, in my experience, it's always something else.

A good scanner will help to read the codes; reset them and retake them to form a 'history'. When my ETA was going bad it pointed to the EA module as well as other items.

A bad wiring harness can, and HAS, taken it's toll on ECUs, so that's a reality.

I'd either have the ETA rebuilt or replaced provided the codes support that conclusion. MENU#24 shows the typical codes that you encounter when the ETA is bad or going bad. I recommend you start there and keep track of the generated codes.

Cool,

This link will show you the thread that led to my question in this thread.http://www.peachparts.com/shopforum/showthread.php?t=179793 Any help is always appreciated.

-thanks,

-Larry

Hello Jim,

Yes, the harness was replaced last year (or maybe the year before). Back then, I had a problem for a while with CAN communication.
Late last year the Air mass sensor was replaced, and things were good for a while...then it didn't want to start when medium warm. The day I took it in to get looked at, it would alternate between barely running or not at all. See my link to my other thread in my reply to cool above.

I'll double check your menu when I get home.
Thanks!

-Larry

Update
 

After doing some thinking and reading, I've decided to get a rebuilt ETA.
Why? Well, because Mercedes-wedontknowanythingaboutcrappywiringharnesses-Benz used the same wiring in the ETA's as well, and I'm not going to take any chances on the ETA ruining other parts, and my ability to use the car. Nor do I feel I can trust the car, especially in an emergency situation, unless I am sure that I have replaced all the parts that might contain the sub-standard wiring MB put into an otherwise great car.

I'll let y'all know what happens after the replacement. (If any of you want to know).

-Larry

Smart move! If you want to be sure before you send it in, take a very sharp 'Xacto' knife and carefully make a cut through the outside sheath for about 4" or so. Carefully spread the cut area open and I'll bet you ($0.10) that you will find crumpled, decayed wires. If it's the "original" ETA, the wires are history.

Update
 

The ETA arrived, and was installed. Still no worky, - now the ASR module is said to be bad.

If it weren't for the fact that I opened up the old ETA, I would've been a little skeptical of that diagnosis.

I opened the side of the ETA that has the gears in it - there is a little trapezoid board on there...the wires under it had NO INSULATION left! None. It's a wonder the car ran at all.

This, seems to answer my question posed in this thread. Yes, a bad ETA can damage modules. So far it is the ASR module that quit - we're not sure about the LH module.


Hope this thread helps somebody.

-Larry

Hopefully you can swap your EA Module (N4/1) with a working unit. That's what I'd recommend.

Thank you for your reply, Jim,

I'm not sure I understand why you think I should swap that one (N4/1).

Supposedly the code reader (a Baum model) claims the ASR module N30/1 is defective. Would a bad EA module give a false reading like that?

Maybe I should try throwing some holy water on it - that way if it catches fire, I know what the problem is for sure. :devil:

-Larry

In all of the ETA failures that I've seen, there are some DTCs that point to the EA Module.

Check my escapade (in MENU#24) with my ETA failure. The codes that were generated were basically three;
1) in the DM (#6 ISC faulty);
2) in the EA (#2 EA plus others faulty)
3) in ABS/ASR module (#30- CAN bus communication failure).

That's where my suggestion came from. . .

If you can also swap the ABS/ASR module, then by all means do so.

hehehe... It was my reading Menu 24 that convinced me to get a new ETA ;)

These ASR modules are not a plenty - I'd search for an EA module, but I don't have the part # (yet).

Update/Question(s)
 

I went and visited the car today.

I hoped that maybe the ETA had not been "reset" before anybody tried to start it. No dice.

Here is what I did notice:

*When turning on the ignition key, there was no whine/buzz coming from the ETA like there had been (no discernable movement either).
*When it did run, it ran all sorts of rich - the exhaust was plenty visible and the air reeked.

Are these symptoms of a bad ASR module or EA module? or both??

thanks!

-Larry

I forgot to mention... 3 base codes are coming up 6, 10, and 17

Larry,
Where did you purchase your rebuilt ETA from? It is possible to get a bad rebuilt unit.

I got it from 4mercedes.com

I notice on the 4mercedes.com site that they claim to have ETA for ASR and Non-ASR. Maybe you should contact them to make sure they did not send you a ETA that is non-ASR. My E420 is non-ASR but you are having ASR issue that would make me suspect to if they swapped the correct ETA rebuilt unit on their shelf. If your ETA does not make any high-pitch noise while ignition key switch is in the #2 position, then it is not working properly. At each start-up the ETA butterfly adjust to the correct position to allow engine to start with the correct air/fuel mixture.

My suggestion is to clear all codes and try starting the engine. Sometime you will get false codes due to the orginal issue from first scan. If the problem still exist the code will occur again.

A fellow member fz500sel, has a '93 400E - I am going to "borrow" his EA module for testing. I'd borrow his ASR module too, but he doesn't have ASR, so I'm out of luck there.
I might give 4mercedes a call too, and make sure he sent the right ETA.

what a freakin nightmare (all because MB used defective wiring - too bad they won't fess up to it - it is costing them their reputation)

Update
 

A bad ETA will not necessarily damage modules.

How do I know? Once I replaced the D.O.A. rebuilt ETA with another rebuilt ETA, the car came back to life.

So the problem was the first ETA was 'bad' . . . DOA???? So did they send you another one that was ok??

As far as your first question, you can consider yourself lucky! :)

Jim,

Yes, they sent another one once I was convinced that it had to be the ETA, and once I convinced the owner (?) that the ETA was Dead On Arrival. He shipped it out pretty quickly. Once I knew the shop had it, I drove over there to see if they had put it in already; they had not, so I grabbed it, and plugged it into the connector and turned the ignition on....I saw it move, and immediately knew that my odds of having my car back, had shot up significantly! Before they could get it into a freed up bay, I started to work on taking out the old one - I think they could tell I wanted my car back lol.

As a side note, the car so far, runs better than ever - no more hesitation. I'm going to drive it a little more tomorrow, to make sure - after driving the 300D for several weeks, getting back into the E420 is almost something akin to culture shock. heh

-Larry

So the first one you got from "4mercedes" was bad?? But the replacement they sent was good??? So you sent the DOA back for their analysis??

Forgive me for asking 'direct' questions but that's how others find out who's who. . .and what's what. . .

Glad you got it fixed. . now you got all that power in your E420. Enjoy!

Jim,
Yes, the first one from 4mercedes was not working. The replacement was good. "Marko" asked me several questions, just to make sure I wasn't grasping at straws, and then gave the order to send another one.
My mechanic will send their bad one back, plus my old one too (he kept it just in case it wasn't the ETA)

Should I ever need to get another ETA, I'll probably get one from them again....except that it will be plugged in and double checked first, before it gets fully installed.

Larry, that's probably one of the best ideas to come from these ETA threads. . . it's so obvious that mostly nobody does it!!!

Plug it in first to test . . but do need to wire the spring onto the throttle plate but that's not hard to rig . . . good idea!

Larry,

Glad to hear you are back on the road. I had a friend who was shipped a bad ETA several times from another company and then he finally order one from a different company that was good. Look like you had the same problem.

Well.....the story hasn't completely ended yet...

Today, the check engine light came on.

Code 10 (MAF voltage too high/low)

The MAF was replaced late last year - Could it be bad already/have gotten damaged by the original (bare wires) ETA?

At least it runs a heck of a lot better!

Funny you should talk about . . .

Checkout MENU#4a . . hot off the presses. You can 'clean' your MAF; see what happens.

At idle you should see about 1.4V or so and about 22Kgm/h flow rate@ 625 engine rpms. Borrow a scanner that does LIVE DATA and check what your MAF reads.

No voltage. . . the wire is open. :(

Also make sure that the hot wire are all connected inside the air mass. If you look down into the air mass with a flashlight, you should see the hot wire connect in three places making a triangular shape. The air mass should have be handle with care doing the removal of the ETA. If the hot wire is not connect in three spots you will need to replace it with a new air mass or a rebuilt one.