Immobilizer Bypass

Kenobi1

New member
I am having a recurring problem with my 2005 sprinter. At first it happened about once every few weeks, but now it is doing it every morning. When I get in my van and turn the key, the motor will crank, the engine will fire, then it shuts down. I get the "start error" message on the dash. I read that this is an Immobilizer problem, and that you can 'trick' the immobilizer by turning the key to position one and then disconnecting then reconnecting the battery. So far this trick works without fail. I really want to get this fixed, I just don't want to drop the $$$$ it cost to replace the immobilizer and re code my keys.

My questions are as follows: 1) has anyone had this problem, and if so, is it indeed the immobilizer? 2) if it is the immobilizer, is there a way to bypass it instead of replacing it? I really don't care if the automatic door locks work. and 3) could this be a battery problem? It only happens for the first start in the morning, and works fine for the rest of the day. I was thinking maybe the battery being old that there is some kind of voltage drop or fluctuation that takes place over night. It seems that if it was the immobilizer this "start error" would occur all the time.

Thanks again for any insight
 

Eric Experience

Well-known member
Ken.
Have you tried your spare key? To check if it is the battery you could try charging the battery for a few minutes before starting. Eric.
 

surlyoldbill

New member
Thanks for the tip on SKREEM bypass. Good to know if I lose my chipped key hiking/camping/running/cycling. One of my biggest dreads is to return to my van from a 10 mile trail run in the middle of nowhere and discover I dropped my key.
 

nebep

Member
When you disconnect the battery you're basically resetting the module. thus clearing whatever the data "fart" is you're experiencing.

if your battery is old, I say start with that - I fixed my transmission with a new battery not long ago - you MUST recognize you're dealing with delicate electronics that don't play well with voltage fluctuations or voltage levels under spec. This is a german vehicle thing...VW/AUDI, and I'd assume BENZ can act all wonky if battery voltage fluctuates or is lower than it should be.

I've been at VW's/Audi's trying to code in keys with no success, then, check out the battery, notice it's low, even though everything seems to be functioning as normal, put some external power on, try again, and everything works as one would expect.

Your "trick" makes sense - you get the truck started - module gets a tad of a voltage boost, then you don't have the problem...The system still recognizes your key, it's just that now it's recognizing it as it should without the drop in voltage and the process is not as visible.

Immobilizer bypass?? don't think so - won't happen. If you drop yer keys in the woods, welp, you're sittin' right where you're at until you:

-- find someone capable (which not many exist because of restrictions to access parts of the programming process needed)

-- tow it to the dealer

-- send me the SKREEM module and a door handle
 

Kenobi1

New member
Thanks for the info. I definately think I'll replace the battery before I start trying to replace the immobilizer. It just doesn't make sense that the immobilizer is shot if it works fine 95% of the time. My van is 5 years old with 290000 miles on it. I own a SuperShuttle franchise and it has only been used in that capacity, which means it's being started and restarted all day long. It could probably use a new battery regardless of the immobilizer problems. I'll let y'all know if it fixes the problem.

As far a bypass, I was thinking a permanent bypass. We have several sprinters in our fleet here in San Diego that don't have immobilizers, at least they don't use the electronic keys, They are all 2004-2006 T1Ns. I figured there might be a way to eliminate the immobilzer and just use regular keys. I know this will make the auto locks inoperable etc, but I don't care.

Anymore insights would be appreciated...
 

surlyoldbill

New member
New OEM spec Bosch battery $99 at Pep Boys
 

nebep

Member
I'm not far from having both of my sprinters on the same key. IF it can be done with two - it can be done with as many as you want.

Even though you don't have the remote integrated key doesn't mean you don't have the immobilizer.

Remotes and immobilizers are two different systems.

Your remote integrated key represents three different "systems" - the mechanical key, the remote, and the immobilizer. They are all separate in their functionality.

If you look at the bottom of the head of your keys that don't have the remote, you should see a small gray "square" - this is where the immobilizer chip is housed. If you're working with multiple vehicles, do a regular check of this to make sure the chip hasn't fallen out. If it does, the truck won't start.

One of mine has the integrated key, the other doesn't. So, my plan is to take the remote key and program that key into the one without the remote and change all the locks mechanically so the same key will work both.
 

dronsin

New member
I have had difficulty in getting spare keys made. This is the issue not with the remote lock entry, but with the key heads that have the rfid chip - which is the immobilizer system. I can get plain keys cut locally, inexpensively.

So, to bypass the system, I dedicated one of my two existing remote fob keys. I have tywrapped it securely in place to act as a permanent rfid chip responder. I removed the circular 'antenna' coil around the ignition switch, inserted and secured an open fob key as pictured, and stowed both in the dash. (this is one of the workaround methods that some remote start systems use)

Now, I can use a plain key and have lots of spares!. If all else fails, I can retrieve the stored key (as in lost key -locked out and AAA access.

Now my second step will be to add a hidden ignition cutout, so I can leave a key permanently in the ignition......and turn it on for valet use. I will also replace the remote entry with an aftermarket and better long distance and multicar useable 'remote' lock/entry system.
Dale

BTW - my sprinter started as a cargo van, and has a complicated door lock control for delivery use. The locks have been a hassle from the beginning. This task above is simply to allow use of inexpensive keys - or trying to get the Dodge dealers to understand how to add a key/avoid the $85 to $275 cost of getting a blank ordered from them, getting them to cut it, getting them to use the DRBII to program an added key, ###&%#@%$%<etc. Like the radio security codes, this all seems a bit over the top - perhaps due to European statutory regs. KISS.
 

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dronsin

New member
Phil,
one way I made two vehicles use a single key was to strip all the tumblers out of one vehicles ignition key cylinder. It then used any key (of same section profile). Who would know, or who would even try.

Again, a KISS simple solution. Dale
 

nebep

Member
Makes perfect sense - I wouldn't do it...and this works if you don't have the rfid chip involved as you do with the Sprinter...Still have to get them both recognizing the same RFID chip....which is doable...

you don't have keep your remote key open for what you're doing with it in the rfid coil. Then the key is "protected" from moving the wrong way and breaking.

Get your key back outta there, take your "vertical" tie and put it completely around the key and RFID coil. This way the coil stays tight to the key - it doesn't take much distance at all and you can get a starting error. These RFID chips transmit a VERY small distance - given the way you have it tied currently, I could see the coil "shifting" not being able to read the key. Make sense?

The other thing you're allowing is if someone wanted to try to crank your truck with a screwdriver - it would start, and stay running.

Then, when your insurance company discovers you had a key rigged like this, you're on the hook, not them.

(This would be revealed after you have been denied access to your vehicle because of a pending investigation by the insurance co's cause and origin guy who specialized in automotive investigations. He'd report back that a key was hidden under the dash so you wouldn't have to use a chip key - then it would be revealed that you kept the OEM security feature from doing its job, then, your claim would be denied!)
 
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surlyoldbill

New member
I experimented with just holding my chipped key close to the ign and tryed starting with a plain key I had made and it didn't work, because of the short broadcast range of the chip.

Possible solution to the fear of losing the chipped key would be to mount a realtor style key lockbox hidden someplace, like in the those lower door panels that I always forget about (I wonder what I put in there last year? I hope it wasn't a sandwich), and keep your chipped key safe and sound in the van, and just use a plain cut key for access. In fact, I think I'll do that.
 

ohlsonmh

Grumpy Member
Nebep wrote:

>"If you look at the bottom of the head of your keys that don't have the remote, you should see a small gray "square" - this is where the immobilizer chip is housed. If you're working with multiple vehicles, do a regular check of this to make sure the chip hasn't fallen out. If it does, the truck won't start."<

Is this something on the outside of the key "fob"? I don't see any such thing on my 4 keys for my 2004

I certainly hope I don't have this "immobilizer" thing ;-)

As Dronsin wrote:

>......"###&%#@%$%<etc. Like the radio security codes, this all seems a bit over the top - perhaps due to European statutory regs. KISS."<

-Oly
 

nebep

Member
You can't see it, but, this is what it looks like. It's inside the head of your key/molded into the key part of your remote integrated key.....

If you have a Sprinter in the US since 2002, and I'm not sure how far back in other places on the planet, your key has this.

(I *think* 1996 or 97 was when immobilizers were required by law in Europe - not 100% sure - maybe a European Sprinter owner could chime in on this...YES, that's a regular sized computer keyboard in the picture for reference sake...As you see, they're small....I get people telling me all the time, "No you clown, I don't want the chip, I just wanna drive my car!!" - "Ok, fair enough, we'll come out, make a key, and that'll be it, see you in an hour or so?" - "Will this cost less?" - "For just the key - yes." - "Ok, come on out!")

SurlyOldBill - I can send you a GE pushbutton combo box with a nice rubber cover to protect it from the elements if you'd like. Just PM me an email address. The combination can be set to a custom number. Small "hitch" with that - lets say your favorite number is 2244 - this won't work - it has to be a combination with four different numbers. IE - 2345. (See pics attached.)
 

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ohlsonmh

Grumpy Member
I have no idea what those pictures are of, but not of any Sprinter key I've seen ;-)

I presume that's one of the chips sitting on your laptop keyboard in #1

Hey, it's no big deal, don't bother with other pics - if they've all had immobilizers since '02, I guess my '04 has it.

Thanks, though! -Oly
 

surlyoldbill

New member
SurlyOldBill - I can send you a GE pushbutton combo box with a nice rubber cover to protect it from the elements if you'd like. Just PM me an email address. The combination can be set to a custom number. Small "hitch" with that - lets say your favorite number is 2244 - this won't work - it has to be a combination with four different numbers. IE - 2345. (See pics attached.)
I can get them locally for pretty cheap, but thanks.
 

nebep

Member
I've had one of those mounted under my 02 since I put it on the road in early 03 - it has stayed there with no problem at all! And yep, it has saved me a few times I must admit!!

Get one!!
 

dronsin

New member
Well, I've been using my non chipped key for a week. Never a problem on startup with the old key and ring antenna stuck under dash. It is just as though nothing existed. Valet parking is no problem either.

Now, I am not sure that there are any truly significant issues with insurance (theft?). I don't think the additional deterrent is any consequence to merit concern. This is not a safety issue to use a plain key - key is still the required 'key'. If someone steals my sprinter by yanking out all the cylinder tumblers and starts it, they are still guilty of the crime. I am not worried about any such issues, it is like the radio codes - overkill.

I am truly happy to have access to aftermarket keys. The factory issues are simply horrible and costly. This removes the whole concern.

As mentioned before, I might add a hidden switch on wires to the antenna, just to make a way for me to control access with a key. I love it.

BTW, this 'always present chip' technique is what some remote start people do as a workaround. It seems to me remote starting of a vehicle engine is fraught with more safety and insurance considerations when the vehicle is not occupied or operated.

Note that the rfid coil antenna and sensing circuit is turned on when the key is inserted, and I believe only active in the start position, so no current or other action happens when running or off! Dale
 

nebep

Member
Remote start installers aren't all created equal.

Some use a bypass box that is energized only when power is applied, as if nothing aftermarket is installed. Usually an "ever present" chip is done by a remote start installer who may not be as well educated as others.

The risk manager in me isn't interested in finding out if my insurance company would bark over the matter or not. I know this fella who ALL HE DOES is work with folks who's insurance companies have denied claims over matters like this. The work he does is VERY interesting - cases where remote install was installed properly, and the insurance company tried to blame that on the theft....Insurance companies rule the world... I've spoken with him multiple times, done some training with him, etc. - It's a real possibility, and if you're willing to take that risk, that's totally up to you. They won't see the screwdriver, they'll see the fact that the truck shouldn't have started by screwdriver, then, deny claim because had the OEM anti-theft system been in place, the screwdriver would not have started the truck. Lets be real as well, I could stand a fair distance away and see that the immo. ring isn't there. There are thieves out there that know what to look for.

As far as "chip interaction" - yes, the reading of the chip is only a "password" - tranferred in nano-seconds from the key to the vehicle. It doesn't keep the vehicle running over any period. Once the chip "work" is done, the vehicle runs until you turn it off.
 

Turbo John

New member
I am having a recurring problem with my 2005 sprinter. At first it happened about once every few weeks, but now it is doing it every morning. When I get in my van and turn the key, the motor will crank, the engine will fire, then it shuts down. I get the "start error" message on the dash. I read that this is an Immobilizer problem, and that you can 'trick' the immobilizer by turning the key to position one and then disconnecting then reconnecting the battery. So far this trick works without fail. I really want to get this fixed, I just don't want to drop the $$$$ it cost to replace the immobilizer and re code my keys.

My questions are as follows: 1) has anyone had this problem, and if so, is it indeed the immobilizer? 2) if it is the immobilizer, is there a way to bypass it instead of replacing it? I really don't care if the automatic door locks work. and 3) could this be a battery problem? It only happens for the first start in the morning, and works fine for the rest of the day. I was thinking maybe the battery being old that there is some kind of voltage drop or fluctuation that takes place over night. It seems that if it was the immobilizer this "start error" would occur all the time.

Thanks again for any insight
There you go.same old problem
 

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