Keyless Go Code: Antenna module malfunction...short circuit to positive.

Old Aug 3, 2024 | 01:57 PM
  #1  
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From: Southern NV
2015 CLS 400
Keyless Go Code: Antenna module malfunction...short circuit to positive.

Hi all, I would really appreciate some guidance on this issue I'm having with my 2015 CLS 400. I've been having intermittent problems with my keyless entry/start functions for about 6 months. Since the heat of summer kicked in (110F+), they have been happening almost daily. I made a dumb move by throwing some parts at the problem before I scanned the car. The code that comes up is N69/5N69/5: The antenna module has a malfunction. There is a short circuit to positive.

Problem: Both key fobs will not lock/unlock doors, keyless start doesn't detect the key. In the morning, when the car is removed from the garage, the keyless system works as expected. All other times it intermittently works.

What I have done so far (one at a time after problem occurred again):
- Replaced batteries in both fobs.
- Replaced auxiliary battery in trunk.
- Replaced original Keyless Go Module(A2129008818) with updated used one bought from ebay (A2129009729).
- This is when I woke up and scanned for codes.
- Swapped original antenna module in the trunk with used one bought from ebay (A2059053005).
- Swapped original antenna module in the rear passenger side door with original from trunk.
- Swapped original antenna module in the rear driver side door with original from rear passenger side door.

The next thing I was going to do was test the wiring from the antennas to the keyless module but I don't have a pinout diagram. Anyone know where I can get that or any other info? The only info I found was a meta description on diag.net when doing a google search for the code description.

It was for a 2015 E63 and it stated "There is a short circuit to positive. Short to positive usually mean KG module A2/39 is not seeing an adequate (too low) voltage value. Since the problem seems ..."

Thanks for your time.

Last edited by emc2kh; Aug 3, 2024 at 04:36 PM.
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Old Sep 2, 2024 | 01:25 PM
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Well it looks like the problem has been solved. Here's what I did:

- Bought a WIS/ASRA image from ebay.
- Tested for voltage drop on all KG grounds. All fine.
- Tested for voltage drop on KG stuff in the rear SAM control unit. All fine.
- Tested the 8 wires that run from the KG module to the 4 antennas for continuity, resistance, short to positive and ground. All fine.
- Bought a used antenna amplifier (A2189055201) from ebay and replaced the original one.
- No Keyless Go problems or codes for 2 weeks and counting. For the last couple of months I've only had a max of 3 days in a row where the KG worked fine.
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Old Sep 2, 2024 | 01:44 PM
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Originally Posted by emc2kh
Hi all, I would really appreciate some guidance on this issue I'm having with my 2015 CLS 400. I've been having intermittent problems with my keyless entry/start functions for about 6 months. Since the heat of summer kicked in (110F+), they have been happening almost daily. I made a dumb move by throwing some parts at the problem before I scanned the car. The code that comes up is N69/5N69/5: The antenna module has a malfunction. There is a short circuit to positive.

Problem: Both key fobs will not lock/unlock doors, keyless start doesn't detect the key. In the morning, when the car is removed from the garage, the keyless system works as expected. All other times it intermittently works.

What I have done so far (one at a time after problem occurred again):
- Replaced batteries in both fobs.
- Replaced auxiliary battery in trunk.
- Replaced original Keyless Go Module(A2129008818) with updated used one bought from ebay (A2129009729).
- This is when I woke up and scanned for codes.
- Swapped original antenna module in the trunk with used one bought from ebay (A2059053005).
- Swapped original antenna module in the rear passenger side door with original from trunk.
- Swapped original antenna module in the rear driver side door with original from rear passenger side door.

The next thing I was going to do was test the wiring from the antennas to the keyless module but I don't have a pinout diagram. Anyone know where I can get that or any other info? The only info I found was a meta description on diag.net when doing a google search for the code description.

It was for a 2015 E63 and it stated "There is a short circuit to positive. Short to positive usually mean KG module A2/39 is not seeing an adequate (too low) voltage value. Since the problem seems ..."

Thanks for your time.
" N69/5N69/5 " is not the normal format of a Fault Code. It is only the name of the ECU. Can you scan again?
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Old Sep 2, 2024 | 01:56 PM
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I am using a BlueDriver scan tool. I have many scan reports and they all state "Keyless Go (N69/5N69/5) Code". Ahh... I forgot the "B154E" part before the description...
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Old Sep 2, 2024 | 02:18 PM
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Originally Posted by emc2kh
I am using a BlueDriver scan tool. I have many scan reports and they all state "Keyless Go (N69/5N69/5) Code". Ahh... I forgot the "B154E" part before the description...
Let's hope everything will be ok, you changed too many parts to draw a conclusion.
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Old Oct 25, 2024 | 12:29 PM
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I have the same problem

[QUOTE=emc2kh;9011347]Всем привет, я был бы очень признателен за руководство по этой проблеме с моим CLS 400 2015 года. У меня периодически возникают проблемы с функциями бесключевого доступа/запуска уже около 6 месяцев. С тех пор как наступила летняя жара (110F+), они возникают почти ежедневно. Я совершил глупость, бросив некоторые детали в проблему, прежде чем просканировать машину. Выдается код N69/5N69/5: неисправность антенного модуля. Короткое замыкание на плюс.

Проблема: оба брелока не запирают/отпирают двери, бесключевой запуск не обнаруживает ключ. Утром, когда машину вывозят из гаража, бесключевая система работает как положено. В остальное время она работает с перебоями.

Что я сделал на данный момент (по очереди после повторного возникновения проблемы):
- Заменил батареи в обоих брелоках.
- Заменил вспомогательную батарею в багажнике.
- Заменил оригинальный модуль Keyless Go (A2129008818) на обновленный бывший в употреблении, купленный на ebay (A2129009729).
- Вот тут я проснулся и просканировал на предмет кодов.
- Заменил оригинальный модуль антенны в багажнике на бывший в употреблении, купленный на ebay (A2059053005).
- Заменил оригинальный модуль антенны в задней двери со стороны пассажира на оригинальный из багажника.
- Заменил оригинальный модуль антенны в задней двери со стороны водителя на оригинальный из задней двери со стороны пассажира.

Следующее, что я собирался сделать, это проверить проводку от антенн до модуля Keyless, но у меня нет схемы распиновки. Кто-нибудь знает, где я могу получить эту или любую другую информацию? Единственная информация, которую я нашел, была метаописание на diag.net при поиске в Google описания кода.

Это было для E63 2015 года, и там говорилось: «Имеется короткое замыкание на плюс. Короткое замыкание на плюс обычно означает, что модуль KG A2/39 не видит адекватного (слишком низкого) значения напряжения. Поскольку проблема кажется ...»

Спасибо за ваше время.[/QUOTE

I have exactly the same error, my Keyless access does not work. I tried replacing the antenna in the driver's rear door, but that didn't help. Please tell me what exactly did you do to solve this problem?
]
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