Smart Key not Found - Help

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shanerrs

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Hello All,

I went to the LR4 2 weeks ago and got the "Smart Key not Found" when trying to start and remote locks would not work.

1- Replaced the Fob Battery
2- Car Battery charged - (3 months old)
3- Codes found using GAP Tool: (so I can't do a deep scan or communicate with the KVM with the tool )

B1B01-87 (2E) Key transponder - Bus signal/message failure - missing a message
U201F-31 (2A) External receiver - Frequency modulation/pulse width modulation failure - no signal

So, looked at many posts here and elsewhere - Suggesting the KVM has gone bad - they are somewhat common

4- I got a used working KMV - and had it cloned to my existing KMV - no issues with that process.
Same Codes.
Clear them.. both KMVs give the same codes.

In between this process,..... water dripped from the A-Pillar - Passenger side (LHD) - CRAP
It was a clogged sunroof drain - no issues with the tube... actually took all the panelling off to check.

5- Checked Wiring to KMV
Good Ground - Black
12V+ to Power - Red
2.5V to Power - Brown (when running)
2.5V to Yellow/Blue - Communication wire (when running)



Next, I am going to replace the Radio Frequency receiver above the driver's seat. Based on the code details and suggested course of action Its 100 CND... so not a expensive test... just waiting for the part - 2 days.

Do you have any other suggestions before I take it to the Indy dealer?

Thanks for the help!



B1B01-87Key Transponder - Missing message
  • This DTC could be logged if 'Smart Key Not Found' warning message is displayed, and the start button is pressed without the key in the correct location as defined in the driver handbook
  • No communication from key transponder during alternative (not passive) start event
  • First confirm that the customer has not performed a start event with the key incorrectly located when the warning message 'Smart Key Not Found' is displayed. Re-synchronize ID by re-configuring the immobilizer antenna unit as a new module. Refer to the electrical circuit diagrams and check the power and ground circuits to the immobilizer antenna unit
U201F-31External Receiver - No signal
  • Communication to the RF receiver module has been lost
  • Refer to the electrical circuit diagrams and check remote keyless entry module circuit for short to power, open circuit, high resistance
  • Check and install a new RF receiver module or keyless vehicle module as required
 

shanerrs

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Replaced the RF receiver - no change -

I am not sure what to do next -

Any ideas before I call my local shop?
 

shanerrs

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Tried both sets of keys and have pulled battery a few times if that’s what you mean by a hard reset
 

ktm525

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true. Hard reset is disconnecting the cables. Touch them together for a few minutes (10) and reinstall. Other than that you have covered all the bases.
 

Rover Range

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Touching the battery cables together is no longer recommended.
On vehicles with the
telematics module, the internal battery will be shorted out.
 

djkaosone

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Hard resets are recommended to "fix" weird electrical issues.

I think there was a missing step to wait 10 minutes prior to battery leads touching in the hard reset procedure previously mentioned.

- Remove both battery leads from the battery posts
- Wait 10 minutes for ecus and other modules to completely drain
- Touch both - / + leads together off the battery posts for 10 seconds
- Mount the leads back on the battery

If you don't wait the full 10 minutes after removing the cables, you run the risk of shorting something out when both battery leads touch.
 

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