Hello all,

I really need some assistance. After installing new front air suspension and control arms I started the car up and went through the procedures to lower it back down. Car was running extremely good, but the air compressor would not kick on. So I (the crazy guy) had the car sitting for about 2 months doing this job (full time service member) and thought I could just reset the computer by taking the battery cables off. I checked all fuses related to the air compressor which where good. I checked all relays which was good, and fully charged the batteries in the process. I removed and install the battery per the Bentley workshop manual and now when I start my car it will run for about 6 seconds and completely cut off (to include all power). Literally the car shuts down, I have to wait a few mins for it to kick back on to remove the key. I can't put the car in neutral to remove it from my garage to even take to a mechanic.

Anybody have any advice or can tell me how to get to a neutral safety switch? I'm assuming the computer (ECU) will have to be reset with deleting whatever codes may be stopping it from starting.

please help you guys I'm at a lost.

 

Try starting with a different key if you have one. Unlikely but could be a bad immobilizer chip in the keyset.

 

Whilst it runs for the small period of time can you put it in nuteral quickly?
Also did it run before the suspension swap?? Can you access a diag machine

 

Hi 08,

I am going to apologize to you in advance because this is going to sound like a lecture. The two areas in your post that I've highlighted are not advisable to do. I see this on so many forums with cars of all types. Somehow, word has gotten around that fault codes can be erased (deleted) and the problems they represent then go away. Unfortunately, disconnecting the battery and/or deleting fault codes only serves to leave the diagnostician further in the dark. Fault codes need to be taken seriously and recognized for the importance they serve.

Now, back to your issue - the first question I have (and need) is - what are those codes? It is difficult to impossible to get anywhere based on what you've written above. The other challenge with online diagnosis is - are the events you describe above exactly what you did or exactly what happened? As an example, if you thought you followed the prescribed instructions for disconnecting the batteries, if you missed any steps or misinterpreted one or more, you could have blown one of the large battery fuses, possibly even the pyro device.

Sorry this isn't much help, but not likely the codes that might have been present exist now since the battery has been disconnected. I hope you can get the car to someone who can now go through a more traditional diagnosis to help you out, but from here and what I read above, I couldn't begin.

All the best in solving it!

 

Yes vehicle ran fine after suspension swap. Air compressor wouldn't kick on so I decided to try and reset the car, due to it being in the garage for so long. after removing the batteries for over 12 hrs and then reinstalled the car will not stay running past 6 seconds. completely shuts down along with all power.

I tried the quick start and put in neutral, but it will not release.

 

I only have one key to start the car.

 

BWing gave you some really solid advice. At this point all you can do is check all your fuses and the pyro device. With only one key you are at a stand still on the immobilizer. Since you need another key anyway I would (if your able) get a new set made then take it to the shop if you don't find any blown fuses that may have been the problem. The pyro, unless you are familiar with how it works, I would leave it to a shop. I have only used my keys once or twice to start my car and I don't think the 05's had push to start. Is it any way you can put the car in "ACC" to get in to go into neutral so you can push it out of the garage so a tow can get to it?

 

Just some info for the mix - sometimes I mix up my Phaeton and Bentley keys (they're exactly the same). If I insert the wrong one, the key won't turn and I get an Immobilizer message on the center dash display. But the car's power stays on.

Maybe a different type of immobilizer error is causing your issue. Something is telling the car to turn itself off for some reason....

 

Remember guys, there are two completely independent electrical circuits at play here. When the key (or push button) is used to start the car, the starter battery (which is isolated from the main battery) is used to start the car. Since you can start the car this would tell me that the starter circuit is probably in tact. Probably the pyro device too. Then, when the key (or button) is released, the starter electrical circuit shuts down and the main battery circuit then continues to "feed" all the systems including the ECUs. Something on the main battery side is failing to keep the systems running.

I suggested checking all of the main fuses. These are the simplest items to check and gets them out of the way. They are located at the main battery (pic below). If you know how to do a continuity check, do that for these 4 fuses across the line and feed sides. If all is good there, then you need to move to other possibilities which are endless and the guessing gets more creative at that point.

I personally wouldn't spend much time on the kessy. This would be a pretty low probability if the Kessy module became corrupted. Anything is possible, but probabilities have to play a part here.

 

B Wings,

Trust me I know I goofed up on removing the batteries lol. But yes the correct procedure was use to remove the batteries per the Bentley workbook I purchased. No pryo was discharged and at all. I have not been able to have the codes read yet, due to the fact that I can not get the car in neutral to get it out the garage and to a shop.

So overall I need advice on finding the neutral safety switch and if anyone know how to test the fuse on the batter cable hook up.

 

B Wing

I will look into this. Any advice on how to check these fuses?

 

I specified that in my post. Do a continuity check line to feed (or both exposed ends of the fuse). If you do not have a meter a simple battery powered continuity test light will work. One lead on one side of the fuse, the other lead on the opposite. If the light lights then the fuse is good.