I've had a 1994 E320 Wagon for about twelve days. It had a clean Carfax report, and I got it for a good deal. I got from Kansas City, MO to Fargo, ND for college without a hitch.

Now, I've got three "idiot lights" ablaze. One of them, the coolant level indicator, goes off and on depending on the time of day or Geraldo Rivera's mood. The first day I drove it home, the excess coolant hose popped off and the car was squirting coolant all over the driveway.

My infernal Check Engine light is on now, and I checked a few rudimentary things to help eliminate a few causes. The Oil is golden, the air filter is clean, and there isn't very much play on the serpentine belt. What could be the cause? I know that if one left the key in the ignition while filling the tank, the car can get a bad read on the fuel level. I think I did that while on the way up once. I filled it up with Premium in hopes of resetting the sensor, but the gas pump stopped and the needle doesn't go over 3/4. Is this the source of my check engine light? And how might I remedy these problems?

The other seems to look like a light bulb, but I'm not sure what it is, as I don't have the owner's manual. It's between the wiper fluid light and the SRS light. If it's a light bulb I can most likely fix myself.

Also, there's a hissing sound coming from underneath the rear of the car when it's running. It sounds similar to an air compressor. What could be the cause of it? Would it have anything to do with the rear suspension?

Thanks,
Chris

1) Reattach the hose with a better clamp. The coolant level sensor is well-known to corrode. Go to MB, buy another one, and change it out. Very simple job. Make sure you have some yellow MB coolant handy to refill the reservoir.

2) Check engine lights could be anything - you need to get the code read by a scanner. Identify the problem, fix the problem. Could be a simple little thing.

3) Bulb is easy.

4) Hissing sound could be your fuel pump working rather than your suspension. Does your suspension sag? Is the self-level working?

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- Brian


1989 500SEL Euro
1966 250SE Cabriolet
1958 BMW Isetta 600

The car rides like a dream, and it seems to be visually level. I know it's a good idea to turn the key to ON without starting to let the fuel pumps start up, then start the car. So, odds are it's the fuel pump?

Do a search on code read tool in this forum. In that car, you can read faulty codes by yourself, after building a $10 very simple tool (thanks to Arthur Dalton). As long as you keep the car you will need this tool.

The bulb, means you have a burned bulb.

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter

I built the tool today and tried it out. I turned the ignition to "ON". I hooked black in pin 1 and red in pin 16. I pushed the button and left it on for 2-4 seconds, and all I got was a solid glow on 5,6,7,8,10, and 14.

Am I doing it wrong?

what kind of button did you install? The circuit needs to close for 3-4 seconds and then open (self release button, normally open). Then it should start to flash the codes. One flash, means no codes but the light should not stay on unless you keep the button pressed.

To read codes, plug black lead into Pin 1 (ground), plug red lead into Pin 16 (12v), plug test lead into Pin XXX (table).Turn ignition on, press switch 2-4 secs, and count the number of flashes. After reading that code, press 2-4 seconds to read the next code, and continue iterating until all codes are read. You'll know all codes are read when you read the first code again. One flash means there are no codes to read.To clear the codes, you must first read the code, then within 10 secs, press the button 6-8 secs.

Some models have a button already installed on position 3 for the DM module.

Attached Thumbnails

   

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter

The 275-1565 button.

It's square, with two prongs on the back.

It's a push on/push off button. I pushed it once to complete the circuit, and left it. It glowed solid for several seconds.

It's because the button. The 275-1556 is a momentary push button which is better for this application. With the button you have, you need to push it on for 3-4 sec and then push it back off to start reading the codes.

I mean, you need to close the circuit for 3-4 sec to ask the module for codes but the circuit needs to open back to start reading the codes.

If you hold the circuit closed for 10 seconds, you delete the first code.

Try pressing the button for 4 seconds and the pressing again to open the circuit and start reading.

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter

Will do. I tried again this morning, but got a solid light on all except 2.

Pin 2 flashed five times. Then, I pressed the #3 button again for four seconds, let go, and it flashed five times. maybe that's my culprit.

What does 5 on pin 2 mean?

Is the engine wiring harness original to the car?


-GH

I think so.

Let me see if I understand. The scan tool has 3 banana plugs. One conected to 1 (ground), one to 16 (12V) and the third conected to port 2? Port 2 must have either a button or an empty hole. There is no circuit asociated to pin 2.

Or does your car have a button on position 2 and a led on position 3? If that's the case and you get code 5 by pressing the button on position 2 (without the scan tool), then the code means "Exaust gas recirculation faulty". If you have this button (on board diagnostics), you only need the tool to read codes for other modules.


Whire harness is very important for that model / year car. Sooner or later it needs to be replaced. MB Wiring Harness Failure

Send me a PM with you e-mail address and I can send you a pdf about analog codes reading.

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter

It has a button on pin 2 and red LED on pin 3. If I recall correctly, I do believe the car was sold in California originally.

Is it the 169 page one? I've got that one. I called my local Mercedes dealer, they said that the EGR faulty might trip itself but be totally fine later. Is there any truth in that? If it comes back on, should I be worried about getting that valve? All it is is a little tube that lets a small portion of exhaust gas into the intake flow, right? After clearing the code, the CEL went off. And it hasn't come back on yet.

I'll send you an email anyways. Thank you for the help.

I got a hose clamp and some yellow coolant, and a taillight bulb. All is well in indicatorlightland.

I'm making a trip from Fargo, ND to Minneapolis, MN tomorrow, and I'll update if anything else comes up.

Thanks guys.

-Chris

Hi,

Yes, it is the 169 pages pdf.

The California version has that button on 2 and led on 3 for the emissions diagnostics. If you deleted the code and didn't come back, you're ok.

This are the codes you read with the DM (pos 2 button)

Emissions - Using Built-in Diagnostic Module
1 No Fault Found
2 Heated oxygen sensor faulty
3 Lambda control faulty
4 Air injection system faulty hot film mass air flow sensor with hot wire
5 Exhaust gas recirculation faulty
6 Idle speed control faulty
7 Ignition system faulty
8 Engine coolant temperature sensor open circuit
9 Intake air temperature sensor, open circuit
10 Voltage at mass air sensor too high/low
11 Tn-signal (rpm signal ) at engine control module faulty
12 Heated oxygen sensor heater circuit open or circuit short
15 Injector, cylinder 2
16 Closed throttle position information faulty
17 Data exchange malfunction between individual control module
18 Adjustable camshaft timing solenoid circuit open or circuit short
19 Injectors circuit open or circuit short emission control module adaptation in engine
control module at limit
20 Vehicle speed signal not present
21 Purge switchover valve circuit open or circuit short
22 Crankshaft position sensor signal faulty
23 Intake manifold pressure (in base module pressure sensor-) with engine running too
high/low.
24 Starter ring gear segments and /or crankshaft position sensor faulty
25 Knock sensors or engine control module faulty
26 Upshift delay faulty
27 Not used
28 Engine coolant temperature sensor (engine coolant temperature change monitor )
44 Not used
45 Fuel safety shut-off electronic accelerator or cruise control active
46 Resonance intake manifold switchover valve
47 Not used
48 Not used
49 Voltage supply at engine control module 8v
50 Engine control module

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Juan
1995 E320 Sedan
2008 Ford Escape
RC Helicopter