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Cell phone

Porsche touts the strength of the built-in phone receiver but when I match the signal strength up to a hand held of the same carrier I get full strength on the hand held and no signal on the built-in phone. The dealer can’t trouble-shoot the problem and now “thinks” that a hand held phone may pick-up signals in certain areas where the built-in phone cannot which does not make much sense to me. Any ideas?

This warranty-related issue should be referred to Porsche Customer Service.
Refer to your Owner’s Manual for contact information.

Are they both on the same provider? Could it be just a difference in the display? I don’t believe there is any standard that says three bars means it is a strong signal or a weak signal. There could be different number of bars showing when both are picking up the exact same signal.

Could be that your car phone provider uses the GSM protocol and your handheld uses CDMA or vice-versa. You might be close to a tower for one and not the other. In any case, your car’s roof antenna should be much more sensitive than your hand held’s. Google “GSM carrier” or check this list.

Maybe you should hang up and drive. It’s a car, not a phone booth.

Thanks for the reply. Yes - both the same provider (AT&T - Cingular). In certain areas I can call out on the hand-held and cannot call out or receive calls on the car phone. I went as far a getting the hand-held from the same carrier just to try and confirm it is an issue with the built-in car phone.

Thanks for the reply and I will check into this, but my intial thought is they are both GSM as the SIM cards are compatible.

Thanks for the reply. Wish it was that simple because it is a great car to drive, but for my line of work a phone is a necessity and hence the attraction to the hands-free feature touted as a superior receiver strength.

Thanks for the reply. Will go this route if the dealership does not come through for me.

Just checked again - both phones as GSM.

Although not obvious in my initial posting the problem is limited to certain areas, but a lot of those areas do not make sense, e.g. greater Burlington, VT where the hand-held is strong and the built-in phone cannot send or receive calls. I had just never heard of the dealership’s theory of the weaker hand-held being able to pick-up certain signals that the built-in receiver considering both phones are on the same carrier with the same GSM technology.

Dealer’s theory is pure BS. The car phone with a mounted antenna should pick up signals much better than a hand held. As far as power for transmitting the hand held has puts out much less strength than an in car unit too.

It is obvious the dealer is clueless on this matter. What isn’t clear is if the Porshe supplied phone is junk or just set up improperly. My guess is the connection to the car mounted antenna has a fault. See if you can disconnect the moounted antenna and try an antenna from Radio Shack. If there is a difference in the phone’s performance then you know the antenna is the problem and have it fixed under warranty.

At the moment the phone seems to be working just about what I’d expect without the antenna hooked up.

Ah ha - More along my lines of thought and thanks for the sanity check. The dealer replaced the antenna, but I have a feeling that the problem is probably somewhere in the wiring back to the receiver. Hopefully, the dealer will come through (they are waiting to hear back from Porsche) as I don’t want to start playing around with the wiring, but in the meantime I wanted to make sure their theory did not hold water.

I’ll bet a car electronics shop, the kind that installs stereo-car phones-remote starters, could have this diagnosed in a jiffy.

Yes, you are probably correct and I may have to go that route and trade-off convenience and efficiency for the hassle of warranty coverage. Enjoy your Sunday.

Another clue to consider. We had occasional problems with OnStar on an 08 vehicle. When I complained, it came out that our unit needed a revised program; this after OnStar was out for years. Ask Porsche if your situation might be similar with your car’s cell phone.

PS, I complained to OnStar, not the dealer.

Thansk - Something I would never thought of.

The most suspect would be the connection between the antenna and the car mounted phone.
Several areas to diagnose; Cable to antenna connection, cable to phone connection, break in the cable somewhere between the phone and antenna, and so on. As has been stated, the car mounted phone should get a much stronger signal with its exterior mounted antenna.
In Mercedes’, we have problems with the antenna cable as it routes up the C pillar. They break in line in almost the exact spot in several cars. A broken wire inside the cable needs special diagnoses, beyond visual inspection. Has the Porsche dealer checked for service bulletins on this?


What was Porsches idea when you needed a phone when you were outside the car,buy a hand held? With BMW the same phone you used outside the car fit into a cradle inside the car.

All hands free operations were activated when you put your portable phone in the in-car cradle.No need for 2 phones (1 portable 1 built in)

Porsche, much like Mercedes, would prefer if you never stepped out…
In car phones are the pinnacle of overindulgence.
But, they are nice.