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Discussion Starter #1
I bought a ML320 as my sons first car...the seller told me it had suddenly quit & that it was the fuel pump. After I got it home I removed the fuel pump & filter, had it tested & all is good. All involved and research on the web suspect key problem.....the key is not making communication with the controller , thus shutting down the fuel pump.
The car starts briefly, a second or 2, then quits....It will do this each time.
I have two keys w/ lock controllers. One never did work, the other locked & unlocked the doors. I tried to sync the bad key as per the owners manual. It did not work....Then I accidently synced the key that did lock/unlock doors and all the alarms suddenly came on and now this key bob won't lock /unlock doors. What have I done?
If I can just get it running...I'm not worried about the remote door lock/unlock.
I understand the VALET key might start it???? I don't have one, but the closest dealer said $60.
How do all these keys work??? The VALET keys must cancel the security system by activating the key switch...my dealer told me the VALET key has an additional notch cut into them...but he would not tell me why.

Any help is greatly appreciated...like I said, I bought this for my sons first car...Don't have a lot of money...and my son will only be allowed to drive 3 miles to school & home....I looks like a safe vehicle.
Thanx,
 

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Purple Moderator
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All keys have a an RFID chip in them including the Valet key.

Depending on your year which you did not post and the exact problem you may have fairly
inexpensive fix for the key issue if they failed.
If it is a 1998 or a 1999 and all 8 keys have been used it is close to $2800 at the dealer to fix. There is a shop in NC that can take care of it at a cost of $1500 if you send them all the relevant parts.
If it is a 2000 or newer you would be looking at the keys/programming, possibly a new AAM module and its programming. The worst would be less than half the amount of a 98-99.

So please fill out your User CP at the link up on the menu bar so we know your year and then we can get you some solid help.

It is a safe vehicle. One save my life or from having a life that would involve home hospice care. The cops were more freaked out the wreckage than I was. I walked away. The 3 people in the Lincoln Town Car that hit me in the drivers door at 40 mph all ended up in the hospital.
 

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Synchronizing the key only enables the locking and unlocking of the doors, etc. and setting the alarm but has nothing to do with starting the vehicle. So for the time being forget about ordering new keys.

In regards to the fuel pump, faulty keys and the like does not shut down the fuel pump. Faulty keys will prevent fuel injectors from operating. Fuel pressure will always be maintained regardless of the issue, except of course if there is a wiring problem or fuse or relay issue.

1. Insert the key into the ignition and turn to position #2, all the time watching the LED light and see that it blinks ONCE. Also do this for the other key. Only those keys which blink once can be used to start the truck. If neither key blinks, you have a huge and expensive problem on your hands.

2. Pull fuse #38 in the underhood fuse/relay box and see that it is not blown. If not reinsert.............

3. With the aid of someone else, crank the engine and probe both contacts on fuse #38 and see that the test light illuminates

4. Using a key that blinks, turn to pos. #2 and with a fuel pressure gauge attached to the fuel rail, check to see that there is a min. of 55 PSI.

Post back with results on each individual test separately. Do not lump all the answers into one paragraph.
 

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Discussion Starter #4
Thank you,everyone for the quick response....I will get the user CP updated, in the meantime , it is a 1998. I will perform the tests now and post back..

Again, thank you so much.....my other option is to load it up on the trailer & take it to Missoula, 35 miles , to the dealer.
 

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re

Consider yourself lucky as my closest dealership is 100 miles away :(

CNB




Thank you,everyone for the quick response....I will get the user CP updated, in the meantime , it is a 1998. I will perform the tests now and post back..

Again, thank you so much.....my other option is to load it up on the trailer & take it to Missoula, 35 miles , to the dealer.
 

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Discussion Starter #6
1st test: failed...no blinking light at all

what is it? Have I just thrown a pile of money at a iron heap????
 

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1st test: failed...no blinking light at all

what is it? Have I just thrown a pile of money at a iron heap????
The seller knew what the issue was and that's why he sold it to you. He knew that it wasn't the fuel pump, but gave you that story so you would bite on the sale.

Your problem is with the AAM (All Activities Module) which has the responsibility of recognizing the keys and then signals the Eng. Control Module to allow the veh. to start and run.

Your two choices are contact the seller and tell him that you had it diagnosed and it isn't a fuel pump, but the AAM which is going to cost approx $2,800 to repair.

The other choice is to bring it to the dealer and have it repaired. But is the cost of the repair and the purchase price below the value of the truck?
 

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Discussion Starter #8 (Edited)
Thanx so much for your time.....even tho I only paid $500 for the truck, I can't afford $2000+ FOR REPAIRS....there are too many miles on this vehicle 200,000+. The sellers were very nice, maybe enuf to work something out or I might just part it out.
I'll look into this module more. I have the fuses and control boxes uncovered...will it hurt to remove them to have a look.....maybe the chip or circuit that is fried is obvious. Maybe a connection is lose or corroded
Thanx again for your help.
 

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If it is a clean truck you will make a lot more than $500 parting it out.
I think 43sqd is right about the previous owner knowing the AAM issue.

Than being said I am sorry you are stuck with this issue. The seats alone are worth more than $500.
 

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Discussion Starter #10
Thanx,,it is a clean vehicle.....one spot of rust on the rear wheelwell.....seats are clean, dash is like new, doors are all good except the front door windows don't operate up or down, but I've worked on similar where it was brushes only in the window motor. Couple dollars and some time

I have all the cotrollers out and the fuse panel and have the AAM removed from the fuse panel....NOW WHAT???? I am not sure I trust the local dealer....what would they do anyway...I already removed the components...they certainly don't repair modules at the dealer.....
I really appreciate the help & support. And, I'm having fun! This vehicle looks like it is built well....and relatively simple to dismantle.
 

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Discussion Starter #11
P.S. Do the keys have to match this AAM, in case I locate a AAM? In other words, do I have to get keys with the AAM? Or is the sync process the way to connect key to AAM...That wouldn't work as then I can go sync to any ML320 which is unlocked.
 

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P.S. Do the keys have to match this AAM, in case I locate a AAM? In other words, do I have to get keys with the AAM? Or is the sync process the way to connect key to AAM...That wouldn't work as then I can go sync to any ML320 which is unlocked.
Other than going to the dealer, the only other possibility would be to find an intact 98 ML 320. From that vehicle you would need.............

1. the ignition lock cylinder.

2. 2 keys with remotes.

3. The transponder ring.

4. The AAM.

5. The Eng. Control Module.

The only draw back with this is if you are only able to get one key, if you ever lose that key you will never be able to get another key made because the chip in the donor remote is specific to the vin # of the donor veh. Since you do not have the title or registration to that veh. M/B will never make a key for you.
 

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You might be able to solve this simply by ordering a new key from a dealer. Full key with remote is about $160 + installation (needs dealer's Star Diagnosis computer). When the key arrives you may have to flatbed it to the dealer according to anti-theft rules. You also have to order it in person.

Sometimes the immobilizer chip in the key loses synch with the AAM. In this case, which is common, both module and keys are good, but one isn't recognizing the other. This usually occurs when attempting start with a near-dead battery or jumpstarting.

The MY1998 is delivered new with 3 keys including the valet, leaving space for 5 additional keys with the original AAM. If your ML hasn't used all 8, you can order a new one. Your dealer can tell you how many you have left.

Keep all your old keys as they can be resynched if you lose (or corrupt) key #8 and need a new AAM. They're not $2800; a member with a MY1998 recently bought a new AAM for $278.40 (less than a fortnight ago).

Call and order the key first, quoting your VIN. You need to take the truck along on the day they deliver the key.

Edit: There is one other possibility - the LED on the dashboard could be bad. If your ECM is really causing fuel shutoff, you shouldn't be getting 2 seconds of idle. You might get 1-2 seconds of crank followed by immediate stall.

Try reinstalling the AAM, synching the previously good remote key, and checking the LED after remote locking.

You should be able to resynch the bad key to enable remote locking. Put in fresh batteries and clean the contacts. If your delivery date was prior to Oct-97, the synch procedure is different. Key to position 2, back to position 0 & remove. Within 60 sec, press and hold down both "lock all" and "un/lock liftgate" simultaneously for at least 15 seconds. Press any button (except "panic") twice. Remote should now work.

If after Oct-97, key to position 2, back & remove. Within 10 sec, press & hold down "lock all", then press "unlock" 5 times in a row. Release "lock all", press any button (except panic) once. Remote should work.
 

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You might be able to solve this simply by ordering a new key from a dealer. Full key with remote is about $160. You can program it yourself, but you may have to flatbed it to the dealer according to anti-theft rules.

Sometimes the immobilizer chip in the key loses synch with the AAM. In this case, which is common, both module and keys are good, but one isn't recognizing the other.This usually occurs when attempting start with a near-dead battery or jumpstarting.

The MY1998 is delivered new with 3 keys including the valet, leaving space for 5 additional keys with the original AAM. If your ML hasn't used all 8, you can order a new one. Your dealer can tell you how many you have left.

Keep all your old keys as they can be resynched if you lose (or corrupt) key #8 and need a new AAM. They're not $2800; a member with a MY1998 recently bought a new AAM for $278.40 (less than a fortnight ago).

Call and order the key first, quoting your VIN. You need to take the truck along on the day they deliver the key.
You cannot order a key without appearing in person presenting the necessary documents. Then when the key arrives you must bring the veh. in and they will insist on doing everything.

Then when they tell you the key will not be accepted by the AAM, they then have you by the short hairs.
 

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I thought that was the policy, but somehow CNB had a brand new AAM arrive by Fedex, and he hasn't gone within 100 miles of a dealer. And that is a TRP.
 

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I thought that was the policy, but somehow CNB had a brand new AAM arrive by Fedex, and he hasn't gone within 100 miles of a dealer. And that is a TRP.
The AAM is not listed as a Theft Relevant Part. CNB received a virgin, un-programmed paper weight.
 

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Discussion Starter #17
Thanx each of you, I will make an attempt today....I cleaned all terminals & the AAM terminals looked especially dirty...maybe I get lucky....
On the lighter side I am wondering if 43sqd ever sleeps???? I see DrX is from Down Under which explains the time of his replies, but 43sqd???? I am worried 'bout you.
Thanx again, now time to go try.
 

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RE

MT Goldminer

The AAM can be purchased for $333 bucks if you purchase a new AAM then in order to program the new AAM a coding key must be ordered. The key cost is $74

depending on if a dealership or Indy does the programing of the AAM the labor cost will vary .

plan on making 2 trips to your local MB dealership

1st to show proof of ownership so key can be ordered

2nd to go back and pick up key and sign for said key

Key can NOT be shipped to you !

CNB
 

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Well, now I have to add more to this mystery....I put everything back together and still the same outcome....the vehicle has no blinking LED.
I decided to check wiring in the dash....I removed the stereo...I removed the casing around the steering column...it seemed to me that this ring (#12 on 43sqd's reply earlier) was awful loose so I unplugged it and removed it....I put the key in the ingnition and turned it on: the doors locked on their own and I got a beeper until I removed the key....I believe this ring around the key switch is the transponder ring. The black cover underneath this transponder ring and over the key switch wiggles but does not turn with the key. The transponder ring, as I said earlier, was loose and turned and moved.

This transponder must work with a magnet in the key switch?????

Can I test it???? Ohms or what? There are two grey wires coming from the ring. and on the other end of a small black box there are 4 pins.
 

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The key should turn. That ring does not lock the ignition switch. Its sole job is the work
with the RFID chip in the key and talk to the AAM with the data exchanged.
 
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