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MG MGF Technical - Strange locking problem

Hi All,

Got a bit of a problem with my 99 F. About a week ago I went to unlock my car to drie to work. Pressed the unlock key on my FOB - nothing. Not a single response from the car. Pressed the FOB a few more times and still nothing happened.

I was a little worried that the car battery may have been flat, so I unlocked the car with the key and check the lights, etc. to see that I had a little juice in the battery. They all lit up so that was good news - especially since I just replaced the car battery a few months back.

Ok, thought the FOB battery may have been flat. I remembered a little tip from Branko some time back who suggested taking the FOB battery out, giving it a rub and replacing which gives just enough juice to unlock the car and immobiliser. Yep, worked great. Drove to the local garage and bought a new battery and all was well.

Until yesterday when I got exactly the same problem above - car would not respond. I had to take the new battery out of the FOB and put it back in. When I did that, the car was fine and worked fine for the rest of the day. THis morning, got ther same problem and had to do the battery in/out trick to get the car started.

I'm a little confused here as I don't think it's a FOB battery issue since the battery is brand new. i also tested my spare FOB just in case it was a failing FOB, but got the same result from my other FOB.

Anyone got any ideas?

Thanks

Sonny
S Foster

Does this happen in different locations, or just one? Does it make any difference if you re-lock and then unlock?

Evidence is pointing towards there being something different in the signal the fob transmits on its first cycle after a battery removal/insertion, AKA a reboot. Try doing the battery 'change' and the first activation of the unlock signal out of range of the car, then try again in range.

Maybe the alarm ECU is what needs the reboot... Disconnect the battery for a few hours and then see if the symptoms persist?
Mike Hankin

<Maybe the alarm ECU is what needs the reboot... Disconnect the battery for a few hours and then see if the symptoms persist?>

Make sure you have your radio security code first!
Ted Newman

Sonny, sounds to me that the electrical contacts in the battery clip inside your key fob have corroded.

I had this problem before in an old key fob - and cleaning the contacts with emery paper periodically did the trick - but in retrospect, I am not sure that this was the best approach. I'd probably try my old favourite trick of using spray-on contact cleaner - less abrasive and hopefully a more durable solution.

HTH
Rob Bell

Sonny,
Is your car a Japanese Import which might suffer the 'Kiwi'problem whereby the Fob frequency is different and suffers from Mobile phone interference ??
Geoff F.
G. Farthing

also, the signal is strongest when you first push, then reduces until the battery recovers, taking it out and giving it a rub may alow it to recover enough to overcome interference, espedially if you sit next to the ariel whilst you do this (the ariel is in
the centre console behind the lamp in the passanger footwell)
Will Munns

Thanks for the advice all. I tried "resetting" the FOB last night with no joy. I'm goin to give the idea of diconnecting the main car battery for a few hours a go to reset the ECU.

I' fairly sure it's not a faulty FOB as I have two FOBs and they are both displaying the same problems. The chances of that happening at exactly the same time are a squillion in one!

I'll let you know how I go.

Cheers

Sonny
Sonny Foster

This thread was discussed between 17/04/2006 and 19/04/2006

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