My left/driver’s door is no longer working for keyless entry or locking by pressing the handle in. It works when I press the fob buttons. My code scanner reports a B1336-13 code, which makes total sense. See the search result I got on that code below.

Since keyless entry works on the passenger door I’m assuming the problem is with something in the circuitry for drivers door and not t the RFA module itself.

My code reader shows this fault code.

B1336M-13 is a Jaguar fault code logged in the Remote Function Actuator (RFA) module — the system responsible for keyless entry, remote locking/unlocking, and passive entry functions.charm

Code Breakdown

The code follows Jaguar's standard DTC format:

• B – Body system code
• 1336 – Specific fault identifier related to the RFA/Remote Keyless Entry Module
• M – Manufacturer-specific code (Jaguar/JLR proprietary, not a generic OBD-II code)
• 13 – Failure type suffix: Circuit Open (indicating an open circuit in the associated component or wiring)

What It Means

This code points to an open circuit fault within the Remote Function Actuator (RFA) module or its associated wiring. The RFA module handles:

• Key fob lock/unlock signals
• Passive entry (door handle touch-to-unlock)
• Trunk/boot release functions
• Hazard light flash confirmation on lock

An open circuit in this system would explain why the car doesn't respond to the fob or handle-touch locking gestures.

Likely Causes

1. Broken or corroded wiring harness connector at the RFA module
2. Faulty RFA module itself
3. Damaged antenna loop circuit (used for passive entry proximity sensing)
4. Low or failing 12V battery causing the module to lose proper voltage

I’m assuming 1and 2 above are not the problem since the passenger door works fine. And I CTEKed the battery to full charge.

That leaves number 3 above as the likely cause. When I start looking at the parts catalog and maintenance manual there seem to be 2 different parts that could be the problem.

One is the Keyless Entry Antenna I show below, either the C2D4232 or the C2D4233. The parts catalog says fit my 2017 S. But the mhz specs are different so I’m assuming they are not interchangeable and I need to figure out which one is correct if this is the faulty part.

https://www.jaguarparts.com/search?s...nna&ptid=20025
When I look at the Workshop manual however I see something called a Low Frequency Antenna

Page 2029 of the Workshop manual shows this.


And page 2033 shows this


C2D4232 or the C2D4233 and not shown in this schematic above.

And page 5832 shows this.

My questions are…

Has anyone else dealt with my problem? What was the solution?

Which of these two antennas is likely to be at fault? The C2Ds or the low frequency ones?

If it is the C2Ds, where are they on the car?

If it is the low frequency one which of the 4 locations applies to the driver’s door and not the passenger door?
Thanks in advance for your help!

 

I had a single sensor go bad. Could only get complete mechanism including exterior handle.My service manager got Jag to pay part I paid labor.

 

I had a failure on the passenger side. It was the wiring, nibbled on by rodents.

 

Code is the left antenna open circuit, best bet would be to test at RFA and verify the circuit first, as there are 3 connections between the RFA and the antenna itself.




Antenna sits on the outside in front of the rear tire, behind the sill trim panel. The wiring runs down the side of the car, into the interior, and across the car.

 

RoverJoe, thanks for the info!

I did some digging and found that the part number for the RFA aka KVM is J9C16073, and I found where it mounts in the car, behind the trim panel on the passenger side foot well.

Since I got a DTC code with my scanner I’m making the assumption that that CAN bus connection to the module is OK.

I’m also assuming that the antenna itself is unlikely to fail.

I think that leaves the most likely causes to be either the wiring from the antenna to the KVM or the KVM itself. Does that make sense?

I don’t know how to test the connectivity between the KVM and antenna since I don’t know what pin the antenna connects to. Does anyone know that? Looks like JLR does not share that.

Claude Sonnet found instructions for how to test the module that I’ll post below for others to see. But it is way beyond my ability and sounds like it requires SDD and a pinout diagram to do most tests, neither of which I have.

I could order a new KVM, but it seems like the dealer would have to install/program it, so might as well let them provide the part.

I could live without passive entry, but the worry is that if the KVM has started to fail it will go completely and leave me stranded.

All this adds up to a trip to the dealer I think.

Any further thoughts anyone wants to share? Thanks in advance.



How To test the KVM

Testing the J9C16073 KVM involves a layered approach — start with basic power/ground checks, then move to communication and component-level tests. Here's a structured guide:

1. Basic Power & Ground Checks (Multimeter)

Before anything else, verify the module is receiving proper supply:

ecumedics(https://ecumedics.com/2025/11/10/lan...ule-solutions/)

- Battery voltage (12V): With ignition off, back-probe the power pins on the KVM connector — you should see ~12V constant supply and ~12V switched ignition feed

- Ground integrity: Check all ground pins for less than 0.1Ω resistance back to chassis ground

- Voltage drop: With the circuit loaded, voltage drop on ground circuits should be under 0.5V

2. CAN Bus Communication Test

The KVM communicates over the vehicle's CAN network, so a loss of CAN signal will prevent it from functioning:

ecumedics(https://ecumedics.com/2025/11/10/lan...ule-solutions/)

- Use a lab scope or multimeter on the CAN High and CAN Low pins — you should see ~2.5V bias with oscillating signals when the ignition is on

- A scan tool (SDD/Pathfinder, Autel, Lonsdor K518) can confirm whether the KVM module is present on the network and responding

youtube( )

- If the module shows no communication DTCs in SDD, the CAN wiring to the module is suspect

3. SDD / Pathfinder Diagnostic Scan

Jaguar's factory tool is the most comprehensive test method:

static.nhtsa(https://static.nhtsa.gov/odi/tsbs/20...96844-1020.pdf)

- Connect SDD or Pathfinder with a Midtronics battery support unit (Jaguar requires this during module diagnostics)

static.nhtsa(https://static.nhtsa.gov/odi/tsbs/20...96844-1020.pdf)

- Run the Passive Entry Passive Start (PEPS) system diagnostic routine to pull any stored DTCs from the KVM

- Use the output control tests in SDD to activate individual components (door antennas, interior antennas) and confirm the KVM is commanding them correctly

help.autosvs(https://help.autosvs.com/kb/land-rov...ort-l494-2017/)

4. Antenna Circuit Tests

The passive entry system relies on the KVM communicating with multiple antennas:

scribd(https://www.scribd.com/document/983898419/Passive-Entry)

- There are exterior door handle antennas and interior cabin antennas — each can be tested for continuity and correct resistance values through the harness

- Check the rear window defroster grid (used as an antenna on some JLR models) for breaks or damage

go-parts(https://www.go-parts.com/garage/ante...oque-2009-2025)

- Antenna circuits should show no open circuit or short to ground

5. Key Fob Validity Test

Before condemning the module itself:

go-parts(https://www.go-parts.com/garage/keyl...oque-2020-2023)

- Replace the key fob battery and retest — a weak battery is a common cause of passive entry failure

- Test with a second known-good key if available

- Use a scan tool to confirm the KVM is seeing the key's transponder signal

6. EEPROM / Flash Integrity (Advanced)

If all wiring checks out but the module still misbehaves, the internal memory may be corrupted:

ecumedics(https://ecumedics.com/2025/11/10/lan...ule-solutions/)

- A specialist can perform EEPROM and Flash memory verification to identify corrupted data sectors

- Services like ECUMedics offer mail-in KVM data extraction and integrity checks if bench-level diagnosis is needed

ecumedics(https://ecumedics.com/2025/11/10/lan...ule-solutions/)

Important: If a scan tool shows the KVM data reads as blank or corrupted, stop further programming attempts — additional writes can make recovery impossible. Send the module to a specialist at that point.

ecumedics(https://ecumedics.com/2025/11/10/lan...ule-solutions/)

 

I highlighted in in my diagram, what pins and wires at the RFA/KVM for the antenna in question.

You should have about 10k ohms I think through those antennas, I would unplug from the RFA and test across that antenna, and then the other side to compare.

Stop posting these AI diag scripts lol

 

Thanks for the additional info!

Doh! I wasn’t thinking apparently, but the color of the wire in the diagram will, of course, match the wire color at one of the 3 plugs into the KVM, right?

Can you share where you accessed that wiring diagram. Did not see anything like that in the Workshop pdf I have.

 

That's from Topix, I have a regular login because I work for JLR, i don't think you can download the whole thing as it's online based and can be changed live.

The connector name/pin# is there, it's connector B so probably the middle one, I'd have to look it up.