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Jaguar B1DC5-93

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Common search variants: B1DC593 · B1DC5 93 · B1DC5_93 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact Jaguar Land Rover service or a qualified repair facility if B1DC5-93 is present or cabin heat is unavailable in EV mode.
Confidence95%

Quick answer

For applicable Jaguar vehicles, DTC B1DC5-93 is documented in the HVAC module and has been associated with no cabin heating while the vehicle is running in EV mode. Jaguar Land Rover stated that the root cause was under investigation in the cited communications.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does B1DC5-93 mean?

For applicable Jaguar vehicles, DTC B1DC5-93 is documented in the HVAC module and has been associated with no cabin heating while the vehicle is running in EV mode. Jaguar Land Rover stated that the root cause was under investigation in the cited communications.

2. Technical explanation

The verified records identify B1DC5-93 as an HVAC-module DTC. The manufacturer communications direct technicians to clear DTCs, run an HVAC-module autoscan, confirm whether B1DC5-93 returns, and read the live-data item “High Voltage Coolant Heater #1 – Overheat Count (22 9A 3C).” A 2018 communication also refers to an approved diagnostic application named “Unlock HV Coolant Heater 1,” followed by verification that the heating and ventilation system operates correctly.

3. What system is affected?

HVAC system; specifically, the verified service information references High Voltage Coolant Heater #1.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • No cabin heating while running the vehicle in EV mode.

6. Possible causes

  • Jaguar Land Rover stated that the root cause was under investigation in the cited SSM75185 communications.
  • Not yet established by verified evidence beyond that statement.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • If cabin heating is unavailable or this code is found, arrange diagnosis by a Jaguar Land Rover service provider or another qualified technician with approved diagnostic equipment.
  • Do not attempt high-voltage coolant-heater unlocking, testing, or repair procedures yourself.

10. Step-by-step troubleshooting

  1. A qualified technician may clear DTCs and perform an HVAC-module autoscan.
  2. A qualified technician may confirm whether B1DC5-93 remains present after the autoscan.
  3. The cited manufacturer procedure calls for reading “High Voltage Coolant Heater #1 – Overheat Count (22 9A 3C)” in live data.
  4. The cited 2018 communication instructs use of the approved “Unlock HV Coolant Heater 1” application, then verification that the heating and ventilation system operates correctly.

11. When to contact service

Contact Jaguar Land Rover service or a qualified repair facility if B1DC5-93 is present or cabin heat is unavailable in EV mode.

12. What the service center may check

  • Check and clear HVAC-module DTCs using Jaguar Land Rover approved diagnostic equipment.
  • Perform an HVAC-module autoscan and check whether B1DC5-93 is still present.
  • Read and record High Voltage Coolant Heater #1 – Overheat Count (22 9A 3C).
  • In the 2018 procedure, complete the approved “Unlock HV Coolant Heater 1” application and verify heating and ventilation operation.

13. Possible repair or resolution

  • No specific parts replacement or permanent repair is established by the supplied verified evidence.
  • The 2018 communication describes completing the “Unlock HV Coolant Heater 1” application and verifying heating and ventilation operation.
  • The 2020 and 2021 SSM75185 communications state that the root cause was under investigation.

14. Affected vehicles

15. Related TSBs / service bulletins

  • SSM74178, published December 10, 2018: “No Cabin Heating Function. DTC B1DC5-4B or B1DC5-93 in HVAC.” It references the “Unlock HV Coolant Heater 1” application and subsequent heating/ventilation verification.
  • SSM75185, published December 15, 2020: documents no cabin heating in EV mode, B1DC5-93 in the HVAC module, and diagnostic collection including heater overheat-count data.
  • SSM75185, published October 13, 2021: documents B1DC5-93 in the HVAC module and the same diagnostic direction; it states the root cause was under investigation.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted manufacturer communications: SSM74178 (MC-10153858-9999), SSM75185 (MC-10185390-0001), and SSM75185 (MC-10202937-0001).

19. Frequently asked questions

What does B1DC5-93 relate to?

Verified evidence places B1DC5-93 in the HVAC module and references High Voltage Coolant Heater #1.

What symptom is documented?

The cited 2020 manufacturer communication documents no cabin heating while the vehicle is running in EV mode.

What is the confirmed root cause?

The cited SSM75185 communications say Jaguar Land Rover was investigating the root cause. A confirmed root cause is not established by the supplied evidence.

Is it safe to drive or charge?

Not yet established by verified evidence.

20. Sources & verification

Verified
Jaguar B1DC5-93:… | EV Diagnostics