96 C280 wont start
 

I am needing some advice.
I own a 1996 C280 with 214,000 miles.
I am having a small problem in starting it. It fires but won't start. The fuel pump has been replaced along with coils, wires and plugs. I have just purshased a new fuel relay. In addition to it not starting, the rearview mirror lights flash, alternating. When it does start, the fuel pump buzzes.
My question, is this a bad fuel pump, a crank shaft sensor or something else?
In addition, I replaced the OVC recently.
Thank you for your advice.
Steve Dale



1996 C280
2001 E430

think FAST

F- are you getting FUEL? disconnect the fuel line connecting to the fuel rail, crank the engine, if fuel comes out, then your fuel pump is probably ok. OR you could check fuel flow at the injectors by pulling them and watching for the spray.

A- are you getting Air? is the air filter clogged?

S- are you getting Spark? use a $5 spark tester to check for spark.

T- is the Timing set properly? check for proper operation of the crank position sensor or something related to timing.

Your no start problem is one of those.

To me "firing" and "starting" are the same thing. You mena it cranks but won't start, or.....???

Flashing Rearview Mirror Lights
 

This probably won't help, but if I recall correctly, the red and green lights alternating on the mirror mean that the security system won't let the car start. This will happen if you get in the car, and use the remote key to lock the doors. You have to wait ten minutes to start the car if you do this. Maybe your security system is on when it shouldn't be.

replay to steve m
 

Thanks for your input. I seem to remember something to that extent, also.
Would you know how or what to check to see if this is the problem? I dont use the remote, the key is old and the the infrared sensor is out. My driverside door will not open with the key, I believe the actuator is out. I lock and unlock the car via the trunk. I did notice a sound coming from the right rear, which i believe to be the cars vacuum system for locks. If you can add any other information, I would appreciate it.
Thanks
Steve Dale

Regarding getting into the car using the key in the trunk and possible security system intervention, I've been doing this for years with my 1997 C36 without problems since the remote transmitter battery died.

I would think that security system intervention would prohibit the car from cranking at all, but I could be wrong.

Best Regards,
Rob

security lights flashing
 

I have been doing the same for years, also. That makes me think the issue is crankshaft and camshaft sensors. Could this be a reason for the flashing security light, alternating?
Thanks for your input
Steve Dale



1985 190E (RIP)
1989 190E (RIP)
1996 C280 214,000
2001 E430 133,000

I doubt a bad crank or cam sensor would result in any kind of flashing/alternating security indicators.

When the crankshaft sensor on my wife's 1999 E320 went bad, the car just wouldn't start. It cranked just fine, but no fire and no blinky lights.

It could be that you've got two separate and unrelated issues. I would recommend disregarding the blinky lights and chasing after the starting problem in a methodical manner (rather than continuing to just throw parts at it).

Are you getting any codes out of the computer?

Steve-

I don't recall for sure what happens when you turn the key while the lights are blinking. This happened 8 years ago the day my daughter got her drivers license. She drove by herself for the first time. When she got back in the car she immediately locked the doors like her Mom told her to. The only way she had ever locked a car was with the remote, so that's how she did it. The car wouldn't start. I came out with a can of gas, but the car started with no problem. She had this problem every day for a week until we figured it out.

I thought it cranked. She doesn't remember. I just tried the same thing in the 97 E420 and the car unlocks itself and starts just fine, with no alternating blinking lights, so they may have changed that system after 96.

The sound you hear from the right rear is the electric vacuum pump that tends to run when there is a vacuum leak - I learned this when one of the climate control vacuum diaphragms stopped working. I tore the whole dash out to get to it. I don't know how the locks work, but if you can seal off the vacuum line that's leaking you might stop that pump from burning out someday (it cost $474 a couple of years ago).

You said you unlock your car from the trunk - how do you lock it? You don't have a passenger door keyhole, do you?

The suggestion that this blinking light thing may be unrelated to a real starting problem sounds completely reasonable. I wonder if these could all be related to a computer problem, maybe related to battery condition or something like that? That vacuum pump would start to run right away, I think, so it may be drawing on the battery at the worst possible moment.

Poking around the forums, I've found threads about a 1996 C280 and a 1995 C220 with no start, cranking and flashing lights- both resolved by replacing K40 relay. Maybe worth looking at.

continued problem
 

Thanks for the input, gentlemen.
I have continued to have the same problem. My mechanic replaced both sensors and we still have the problem. It will start, but not turn over. The lights continue to flash.
In addition, the codes we get are from a Snap-On reader, they indicate air temp at 312, without any air flowing and water temp at 416, without the engine on.
He checked the injectors and they are not pulsing, although it is getting fuel.
We think it is a computer issue, but now are running out of ideas.
I wonder about a new key. The old one no longer sends a signal.
In answer to your question about unlocking the car thru the trunk, yes, I unlock and lock the car via the trunk, with no major issues, still does that today.
I have changed all relays and sensors I know off. This K40 relay, I have no idae about. If you would, inform me what this is.
Any other ideas would be greatly appreciated.
Thanks

I am kind of confused on your statement. You say it will start but won't turn over? Not sure what that means?? Not for sure if it would help or not, but have you tried disconnecting DC from it. Then reconnecting DC to see if it will start.

stranger then truth
 

Well, my mechanic replaced both sensors and the car has started without any problems since late April. It is now mid June and the same problem has returned.
The security lights continue to flash alternatingly, it will start, but not turnover. I can tell whether it will turnover when I turn the key to the 2 position and I can hear the fuel pump kick in, then I can continue to turn the key and the car will start.
Surprisingly, this situation has happened multiple times this week. Once it took and hour before it kicked over, another 30 minutes and this morning I quite after 10 minutes, out of frustration.
As I have mentioned, the sensors, fuel relay, ovc relay, fuel pump, plugs, wires, coils, battery, starter, fuel filter, mass air sensor have all been replaced in the last year.
I am open for suggestions.
It pulls no codes and Benz techs don't know what the issue is without forcing me into bankruptcy.
I appreciate your input on this matter.
Steve Dale

I had the same problem with the same car - somehow I compressed key fob while trying to start the car and this somehow disabled the ignition (assume it is an anti theft device). As I recall, the fix was to lock the car with key and then unlock it. If that doesn't work, locking and unlocking the car with fob vice the key worked on my 85 Porsche.
Socks E420

I was going to mention this same sort of thing as well. IIRC the alternate flashing red and green lights means that there is no start authorization. Either that or the battery in the key is weak, but also IIRC the battery is not required to get start authorization, so a bit confusing, although I think I do have a training manual for the older DAS systems so could look it up.
IN the meantime, do you have a second key you can switch to as a test? Could also be a problem with DAS on the car, like the DAS module or transponder ring (antenna ring) around the key, if this style has that.
Gilly

(Found my training guide)
All 96 Mercedes used DAS2 immobilizer.
The alternate red/green lights do signal an unauthorized start attempt.
The engine control module is disabled in an unauthorized attempt. Since the control system is ME-SFI, I am unsure what is disabled, but would have to be spark or injection or both, the fuel pump might still operate as you've noticed.
The system is set whenever the car is locked, either with the remote or key blade (I know you said the remote is inop).
There is no antenna on the ignition lock, what I mentioned before about that is wrong, that came a year later.
DAS is controled by the remote central locking control module (RCL). If this proves to be the problem it will need to be purchased new, as the RCL is "mated" to the engine control module, you can't just buy a used one.
I don't know if it could one of the unlock switches in the car causing this? It would be "interesting" to find out if the remote central locking working (new working key) would fix the problem or not.
If someone with a shop computer (probably a dealer) could monitor the system, this should give some idea of why the start process is being disabled by DAS, or there might be codes stored telling where the problem is. Some of the security functions on the car can only be accessed by a dealer, you can ask the dealer if they can simply do a "quick test" of the control modules on the car and ask for a printout. The problem possibly could be with the drivers door lock not working properly, would be my first guess.

Steve, just noticed, if the start is authorized the result is no fuel injection. The pump might still run, but the injectors don't squirt.

another idea
 

Gilly, thank for your expertise!
You are correct about the ring around the igntion switch. Mine is an 06/96. The 97 models have the sensors.
Now, you hit on something.
I have the driveside door that will not lock or unlock, thought it was the actuator, but now think it could be something else. Any ideas?
I had trouble with the car again yesterday, but I tried putting the key in, and I know this will sound silly, so as to scrape the top and over right side of the ignition entrance as I insert it. Low and behold, it started! Tried it again and it continues to work!
Now my question is, since this is an electronic switch, could it be the ignition connections inside the switch?
I also can, on rare occasions, get my dash to come up and work if I turn the key in right manner. This seems to be related to the ignition as well.
I have found ignition switches on Ebay, don't know what they are, exactly, but would a replacement of the 7 pin switch be a possible solution?http://cgi.ebay.com/Mercedes-Benz-Ignition-Switch-240D-280CE-280E-300D-300E-/170463511640?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3AC280&hash=item27b06ac458
Your assistance is greatly appreciated!
Steve Dale

Steve, I don't think that's the right style switch. It could be suspect, if it is the style I think it is, I've posted to several people aout the suspicion I always have of this style switch.
My immediate reaction is that there is I believe an electrical switch in by the door lock which I would also be suspicious of, especially if you have a problem with the drivers door lock anyways. This switch is what would signal the DAS to let the car start.

So, Gully, what is this sensor in the door? Can it be replaced?
My mechanic is quite sufficient if I can get the right part. I will also check with the Benz house to see about the ignition switch and what is in the door. Can u tell me what a DAS is?
Thank u for Ur diligence in this matter. I truly love this car and other then this issue it is in wonderful condirion. I have taken great care with this car and want to continue to drive it. Your assistance is so appreciated.
Steve Dale

Sorry, Gilly. Stupid phone.
I also need to add that the door will lock and unlock via the trunk, so the actuator appears to be working. Let me know if their is an electronic sensor or something of that nature inside the door.
Thanks again
Steve Dale

Steve
IIRC it isn't a sensor so much as a switch, and also IIRC it is on the side of the door lock cylinder, inside the door. The fact that the drivers door lock isn't working and you have this no-start problem could all be related. I believe the switch is available as a seperate item. Again it might be worth it to get it all working, I don't think the key costs all that much on this car, I'm sure you'd love having a remote again! To work on just the outer handle and lock cylinder I don't think the inner door panel even needs to come off! But to get it locking and unlocking again from that door (using the key) probably will, I think it's just a metal rod, may have become disconnected, this happens some times, say if someone uses a slimjim to get in the car (like for example the keys get locked inside).
DAS is Driver Authorization System, in other words in the antiotheft system, which is keeping the car from starting. It is not a single component, it's just the nomenclature MB uses for the antitheft system. DAS2 is the "type" of DAS you have, there are/were various versions of it, DAS1, 2 and 3 and another one called DASX, I am sure it is all different today. They mainly change the systems to keep the crooks on their toes.

Gilly, I was hoping you would think this might resolve my situation.
I am starting to get very frustrated with this. I have searched three forums and found every thread and read every post, it seems that no one knows what to do about this. Is this true?!
I have read about changing out ECU, other components and nothing seemed to resolve this matter.
I really want to find the answer, not just for me but for all the others that are or have had this issue.
I read a thread on the door lock for this car on this forum. Mentioned pelling back the rubber seal to reveal the lock and finding some pin the had come out.
I will have my mechanic do this repair and see if it remedies the problem.
You are right, I would love to have this lock working again, then get a new key.
Other then this no-start issue, my car is in great shape, in and out. I just want it to operate without the fear of not starting.
I will get the repair done nxt wk., too late to get it to him and have it done this wk. I will let you know the outcome.
If there is anything else you think of that might be a factor, please pass it on and I will attempt to have it done.
Thank you so much for your information and help!
Steve Dale
Lubbock, Tx

Steve, it sort of makes sense, at least because of the red and green blinking lights in the mirror, that means that DAS says "no authorization" so that explains the crank but no start. IF the mechanic can read the codes in DAS it might even say that it is due to a problem with the drivers door lock. The mechanic might not be able to read DAS codes as MB is very fussy about letting out security info to the code reader companies.

He can't read those codes, at least I don't believe he can. Nevertheless, we will have the door lock work done nxt wk. I will get the car to him today, somehow.
I found the thread on the repair. Looks ominous, but I trust his abilities. He has been taking care of my Benz's for years. He will get the job done and I will let you know the outcome.
Have a marvelous Father's Day!
Steve Dale
Sportsline

OVP
 

Well good morning! And a good one it is!
Last week my mechanic took it upon himself to get a new OVP.
Well, the car started and has started ever since!
Now, I had replaced this item about 3 years ago with the new number.
I take it that this has something to do with the fuel supply or electronic release of the security system.
What all does the OVP have charge over?
Nonetheless, the car has been running great. Had the lower control arm bushings replaced and the ride is back also.
The door lock still wont work, but that's a problem for another day. Perhaps when I order my new key in August. On vacation for July,will worry about that then.
Thanks for your diligence and knowledge. I could never have remedied this without your assistance.
Steve Dale
Sportsline

Sounds good, just hope it continues to work for you.
The thing is, is I didn't think the 96 202 even has an OVP, I thought it had the "next" thing that does the OVP job, which is the K40 relay.
At any rate the OVP protects the control modules from over voltage (Over Voltage Protection relay), in case like a jump start, or even from reverse polarity. The OVP on the older CIS cars could cause poor running or various systems to stop functioning like ABS.
I am still skeptical of the whole repair as the red/green lights were alternating which was obviously why the car was not starting. So I think you are heading in to a time period where it will work for you, but more to come later. Probably all linked to DAS and the drivers door lock not working. So sorry to rain on your parade, just calling it as i see it.

thanks
 

Thanks, Gilly. I will repair the doorlock when I get back from vacation. Will be gone for July, will get it done as soon as I get back. Early August, should be the timeline and will keep you informed as to the result.
All I know is my car is running now and that's all I was asking for.
Other then the doorlock, the C280 is in wonderful condition. Just a bit worse for having 216,000 miles on it, LOL.
Thank for your help and I will let you know the result of the doorlock repair when I return in August.
Steve Dale
Sportsline

Sounds good Steve, hey I may be all wet on this too. It just seems like the problem has already been known to "fix itself" for quite a while, then reappear. Maybe it really IS fixed this time, but if it reappears, then I would look further in to the DAS system and the drivers door lock not functioning.
I would really like to think that having the remote working would be enough in and of itself to at least get the new key, I think most of us are spoiled by the new cars with their remote unlock systems. I know I restored an 84 BMW 325E a few years ago without of course remote unlocking and remember thinking "OH I have to unlock the car with the KEY, how quaint!"

keyless
 

I defintely will get the doorlock done and a new key. You're right about the keyless entry. My wife's E class has it and I love how easy it is. Since mine has it, might as well use it.
Talk to you in August when I get the work done.
Thanks again.
Steve Dale
Sportsline