Mating ECU to Throttle Actuator 1992 400e - PeachParts Mercedes-Benz Forum

mespe · #1 01-01-2007, 07:49 PM

How does one mate the ECU to the throttle actuator on a 1992 400e.

I read the manual and I believe it states to simply turn the ignition on for 90 seconds without starting the car.

I've tried that, but I get no results.

I put a new ECU in my car, turned the ignition on without starting the car, waited 90 seconds (probably more on atleast one occassion) but all I get is an idle. Accelerator peday in non-responsive.

Thanks in advance

Marty

mespe · #2 01-02-2007, 11:13 PM

anyone?

deanyel · #3 01-02-2007, 11:39 PM

Which manual? Are you getting any fault codes now?

myarmar · #4 01-03-2007, 12:01 AM

Marty, I'm not familiar with your car. Is it LH? If it is, I don't think you need to mate control module to the ETA. That procedure is for controle module to learn throttle travel from closed to open position. You should hear the humming noise as ETA moves. Even if you did not do it ETA still should work, but you may get too low or too high idle speed.
Did you check your ETA harness? Maybe short there disables output driver in the control module. Also check fuses in the Base Module.
Good luck, Mike

pcmaher · #5 01-03-2007, 08:32 AM

I had to go through the "learning" process too. Mike came through for me, and gave me this info...

Once the ETA is installed and re-connected to it's mating connector, you will need to allow the ETA to "relearn" idle and full throttle positions.
1) Turn ignition to position 2 (all dash lights are lit), DO NOT Start engine!
2) Wait 60 - 90 seconds. The electrical motor of the ETA will cycle through it's range of motion, and relearn the idle and full throttle positions.
3) Turn the ignition off. Wait 2 minutes.
4) Start car to test performance of ETA.

You may have to do this many times. I found that my car re-learned over a period of a few weeks! I had an abnormal surging at idle for a few days until the ETA relearned it's positions. It corrected itself over a period of a couple weeks.

mespe · #6 01-03-2007, 10:21 PM

Myarmar,

Yes it is an LH. After I installed the ECU and did th 'learn' procedure,,, 90 seconds position 2 no start,,, several times All I got was the engine cycling between 800 and 1500 RPM at about 1 hertz. this slowly decreased to almost a steady idle after a few seconds (30-60). But absolutely no response from the accelerator pedal.

now I thought that if the car goes into Limp home mode, it's throttle by cable, but apparantly I didn;t even have throttle by cable as whenever I depressed the accelerator pedal I got NO response whatsoever.

It's goona be 50+ degrees tomorrow, so I might try again.

Interesting side note, with the original ECU I get the same cycling, but not as drastic.

JimF · #7 01-04-2007, 11:11 AM

Can you say . . . . ETA??? See Menu#24 for some ideas . .

mespe · #8 01-04-2007, 04:17 PM

Played with it again today,,,

When I first started the car (after replacing the ECU) I noticed that the cycling, the first time the RPM's get to about 2200, then down to 800 then up to 1800 down to 800, up to 1500, down to 800, up to 1200,,,, it finally idled at about 1050 RPM. Put the car in gear and the cycling stopped, and the engine purred at 750RPM.

BUT the accelerator pedal was inoperative. I repeated the "Learn" process, but allways the same results.

After the car warmed up a little (40C) the peek RPM on the cycle was down to around 1200 RPM,, no accelerator pedal response still. I went under the hood and manually pulled on the accelerator cable, still nothing, not even L-H mode thorttle by cable.

Put the Old ECU back in and everything is back to the way it was Cycling about +/-100 RPM at the same one second interval, but teh gas pedal does work.

Why doesn't the throttle-by-cable work for the new ECU?

JimF · #9 01-04-2007, 05:30 PM

Quote:

Originally Posted by mespe

Put the Old ECU back in and everything is back to the way it was Cycling about +/-100 RPM at the same one second interval, but teh gas pedal does work.

Why doesn't the throttle-by-cable work for the new ECU?

Good question?? A WAG is that the new one is not compatible or, if it is, it's not operating correctly.

To test that, find another car same as your 400E and swap it out. Also swap your own ECU and those two (2) tests will fill in a piece of the puzzle and may point you in the correct direction!

myarmar · #10 01-04-2007, 07:20 PM

Maybe something wrong with your throttle cable adjustment? Limp mode is strictly mechanical, and requires more pedal travel before throttle actually opens. It also limits full throttle to about 2/3 of normal. You can see that with ignition OFF. Remove air filter housing and look down through the AMM while somebody depressing accelerator. If everything looks good, turn ignition ON and repeat the test. You should see full travel even without starting the engine. Don't use throttle cable or lever in the engine compartment to open throttle. That would put it in the limp home mode.

mespe · #11 01-05-2007, 10:38 PM

Don't think the throttle adjustment matters in this case, as I manually moved the throttle to fully open and no increase in idle speed.

JimF,,, I can say ETA but I don't want too. (well I'm looking into one that was mated to the ECU I bought.)

JimF · #12 01-05-2007, 11:43 PM

Quote:

Originally Posted by mespe

JimF,,, I can say ETA but I don't want too.

Don't blame you about that!

Do the parts swapping and that should give you a clear direction to follow. . . hopefully?