I have been having trouble with my r172 key fob working only via IR (when pointed to the black square on the handle)and opening/closing the car via the touch sensor on the door handle.
I do have a smarttop SHTFMZ2 and miss being able to tap the remote 3 time and have it open as I walk to the car.
RF used to work until I removed and replaced the fuse to supply power to my blackvue dash cam. Yes the fuse is providing power to both pins, tested both pins with meter for continuity and voltage when plugged in.
The RF does not work at all with both keys, I have changed the batteries, tried all of the reset procedures I could find on searching forums (Listed Below) none seemed to work.
Am I missing something? Are any of these procedures for the current R172 model cars?
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option 1
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1) Place your key in the car's ignition and turn the key two clicks to the "On" position for any Mercedes car.
2) Press and release the lock button on your Mercedes keyless remote.
3) Press and hold the unlock button on your remote.
4) Press the lock button on your remote five times consecutively, while the unlock button is still held, at one or two second intervals.
5) Release the two buttons and wait five seconds after pressing the lock button for the fifth time.
6) Press either the lock or unlock button once to finish the programming sequence.
Read more :
How to Reprogram a Mercedes Remote | eHow
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option 2
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My mechanic friend came by this morning and resync the key (2005 S55 keyless go). It works now. However he uses a different programming procedure than what was provided. Here is what he did.
1) put key into ignition and turn to position 1
2) hold lock button for 5 seconds
3) hold unlock button for 5 seconds
4) hold both lock and unlock for 5 seconds
repeat steps above in position 2.
Everything is working as it should. Keyless go, RF lock/unlock. Previously both my keys were not working but after this procedure (1 key) both keys are now fully functional again.
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option 3
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There are instruction in it to synchronize the remote.
1) Aim the remote eye at car and depressing both the lock and unlock buttons at the same time twice
2) Insert the key in the switch with in 30 seconds and turning it to posistion 2.
Make sure you only do this after you are able to get inside the car.
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option 4
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Here are the instructions:
"Place the key in the ignition., turn to position 2 and push the unlock button on the fob, repeat for the lock button. Turn to position 0 and remove the key. Both buttons should work."
But first I would check if the red light on the key fob flashes when you press and hold the buttons! If it is then it's just the issue of reprogramming (I would suggest).
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option 5
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Key synchronization Procedures
SL Models
90-95 see note 1
96 see note 3
97 see note 2
98-99 see note 4
S-Class Models
92-95 see note 1
96 see note 3
97 see note 2
98-99 see note 4
C-Class, CLK, E-Class
96 See note 3
97 See note 2
98 –99 see note 7
SLK
See note 4
M-Class
Early 98 Models up to A010609
With original AAM and keys see note 5
Later models 98-99 after A010609 see note 6
Note: All M-Class keys require the HHT for Initial Installation
Note 1: Aim transmitter at a receiver and briefly press any transmit button. Within 30 seconds, lock or unlock car at a door or trunk with the new master key.
Note 2: Aim transmitter at a receiver and briefly press the transmit button twice. Within 30 seconds, insert new key in steering lock and turn to position 2.
Note 3: Aim transmitter at inside rear view mirror receiver and briefly press transmit button twice. Within 30 seconds, insert key in the steering lock and turn to position 2.
Note 4: Aim transmitter at vehicle and briefly press the lock or unlock transmit button twice. Within 30 seconds, insert key in steering lock and turn to position 2.
Note 5: Turn key in steering lock to position 2, then to position 0 and remove. Within 60 seconds, push and hold the lock button for 15 seconds, now push unlock button 5 times. Then check all functions.
Note 6: turn key in steering lock to position 2, then to position 0 and remove. Within 60 seconds, press the lock and tailgate buttons simultaneously for 15 seconds.
Note 7: For Smart key equipped vehicles, simply insert key in the ignition switch and follow info in the cluster display
