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disengage immobiliser

Hi

Mercedes 300E 1996 diesel. I cannot start my car because the immobiliser will not disengage. I have changed the batteries in the key fob, I have tested them to see if the IR light comes on and the recovery mechanic checked them on his machine. I have checked the manual to synchronise the sender/receiver (press fob twice) and its still no good (my spare key is only 6 months old, it cost me £120). When I turn on the ignition I get red/green flashing at the rear mirror receiver. The car cranks OK but will not fire. Is there anything I can do before I call out Mercedes tomorrow? I know one they are on the case it will cost me a fortune. In case it is relevant, the car is kept in a dry garage and is only used about once a fortnight.

TIA

Charlie Brown

Reply to
Charlie Brown
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Make sure your battery on the car is in good shape... if it is old or weak, you will get lots of problem. Check voltage and do a battery test.

Reply to
Tiger

Another thing... is your glow plug light lighting up as normal? Immobilizer usually won't let you crank the engine at all.

Reply to
Tiger

tiger

My battery is about 3 years old, although untested , it has been OK and starts the car first shot after 2 weeks idle. It is flat today though, after flogging it yesterday. the glow plug light works OK. I am in danger of calling Mercedes very soon!

Charlie Brown

Reply to
Charlie Brown

I don't think it is the immobiliser that is preventing you from starting... If you could... hook up a jumper cable to another car as usual and let that car run... about 2000 rpm.

On your car... try starting with petrol pedal fully depressed... after the glow plug light goes out. If it does attempt to fire up, the keep going. Do not crank for more than 45 seconds at a time. and let 5 minutes to cool down the starter.

If it still does not attempt to start... are you sure you got enough diesel in the tank? Maybe it could be your fuel pump.

Reply to
Tiger

Tiger

Mercedes are rubbing their hands together as we speak. It was towed away this morning with a completely flat battery. I will get myself a jump start/charger unit this weekend. there was no juice left to do anything more. Thanks for your help. I will get back with their solution later.

Charlie Brown

Reply to
Charlie Brown

I hope you used the services of a motoring organisation if you were appropriately covered. The tow should be free then.

Did it a few months ago. Could have had a tow (well, transport on the back of a lorry) under the Mercedes Mobilo Life scheme but it would cost if not a manufacturing fault (which it wasn't) so used the RAC. Saved 120 quid, IIRC.

DAS

For direct contact replace nospam with schmetterling

Reply to
Dori A Schmetterling

Dori

Absolutely right. I was hoping that Mercedes would send an engineer to me with a computer or gadget to bypass the immobiliser. They said they don't do that anymore as all non starters are collected by a tow firm under contract. They would have billed me for the transport cost to their nearest distributor. Luckily I was covered by . FYI, the problem is the result of a faulty K40 relay switch - total cost £300!

Charlie Brown

Reply to
Charlie Brown

All

the flashing immobiliser was a symptom of the problem. The failed K40 relay switch shut off power to the fuel pump and because of the power failure, the immobilser lights flashed because they were on the same circuit. This is explained as best as I understand it.

HTH

Charlie Brown

Reply to
Charlie Brown

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