B1273 Lexus Code - Sliding Roof ECU Communication Stop
Quick Answer
This Diagnostic Trouble Code (DTC) is stored when Local Interconnect Network (LIN) communication between the sliding roof drive gear sub-assembly and Main Body ECU (Multiplex Network Body ECU) stops for 10 seconds or more. Common causes include Faulty Sliding roof drive gear sub-assembly, Faulty Main Body ECU (Multiplex Network Body ECU), Main Body ECU harness is open or shorted. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
- What it means
- B1273 Lexus indicates Sliding Roof ECU Communication Stop.
- Common causes
- Common causes include Faulty Sliding roof drive gear sub-assembly, Faulty Main Body ECU (Multiplex Network Body ECU), Main Body ECU harness is open or shorted.
- Severity
- Low - monitor the vehicle and repair when practical.
- Can I drive?
- The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
Code B1273 Lexus Description
What are the Possible Causes of the DTC B1273 Lexus?
- Faulty Sliding roof drive gear sub-assembly
- Faulty Main Body ECU (Multiplex Network Body ECU)
- Main Body ECU harness is open or shorted
- Main Body ECU circuit poor electrical connection
How to Fix the DTC B1273 Lexus?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B1273 Lexus code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about B1273 Lexus Code
1. What are the common symptoms of OBDII code B1273 in a Lexus related to the Sliding Roof ECU Communication Stop?
- The common symptoms include the sliding roof not operating correctly, unusual noises from the roof mechanism, or the roof getting stuck in one position.
2. What are some possible causes of the Sliding Roof ECU Communication Stop issue with code B1273 on a Lexus?
- Potential causes may include a faulty sliding roof ECU, damaged wiring or connectors in the roof system, or a communication breakdown between the ECU and other components.
3. How can I diagnose the Sliding Roof ECU Communication Stop problem with OBDII code B1273 in my Lexus?
- Diagnosis typically involves using a diagnostic scanner to retrieve the specific code, inspecting the roof ECU and related wiring for any visible damage, and performing a communication test to identify the issue.
4. Can I still drive my Lexus safely with the B1273 code related to Sliding Roof ECU Communication Stop?
- It is generally safe to drive the vehicle with this code, but you may experience issues with the sliding roof functionality. It is recommended to address the problem promptly to avoid further complications.
5. What are some DIY repair tips for resolving the B1273 code linked to Sliding Roof ECU Communication Stop in a Lexus?
- DIY repair tips may include checking and repairing any damaged wiring or connectors, ensuring the roof mechanism is free of obstructions, and resetting the ECU by disconnecting the battery for a few minutes.
6. Is it necessary to visit a mechanic for fixing the Sliding Roof ECU Communication Stop problem with code B1273 in my Lexus?
- While some simple troubleshooting and repairs can be done at home, it is advisable to consult a qualified mechanic for a thorough diagnosis and proper repair of the sliding roof ECU communication issue.
7. How much does it typically cost to repair the Sliding Roof ECU Communication Stop fault with OBDII code B1273 in a Lexus?
- Repair costs can vary depending on the underlying cause of the issue. It is recommended to obtain a diagnosis from a mechanic to determine the exact repair needed and associated costs.
8. Can weather conditions or moisture play a role in triggering the B1273 code related to Sliding Roof ECU Communication Stop in a Lexus?
- Yes, extreme weather conditions or moisture exposure can sometimes lead to electrical issues in the sliding roof system, potentially triggering the communication stop fault and setting the B1273 code.
9. Are there any preventive maintenance measures to avoid encountering the Sliding Roof ECU Communication Stop problem with code B1273 in a Lexus?
- Regularly inspecting the sliding roof system for any signs of wear or damage, keeping the roof tracks clean and lubricated, and addressing any minor issues promptly can help prevent the occurrence of this fault.
10. How urgent is it to address the Sliding Roof ECU Communication Stop issue with OBDII code B1273 in a Lexus?
- While it may not pose an immediate safety risk, addressing the issue promptly is advisable to ensure the proper functioning of the sliding roof system and prevent potential inconvenience or further damage.
Discuss the causes and fixes for B1273 Lexus OBDII Code
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The B1273 code on your 2011 Lexus IS250 indicates a communication issue with the Sliding Roof ECU, which controls the retractable hardtop operation. Since your windows go down but the top doesn’t retract, the system is likely encountering a fault that prevents full operation.
Possible Causes:
- Roof Position Sensors Faulty or Misaligned – The retractable top relies on position sensors to ensure proper sequencing. A faulty or misaligned sensor can interrupt the process.
- Weak Battery or Electrical Issue – Convertible tops require strong voltage to operate. A weak battery, bad ground, or corroded connection could be causing the issue.
- Faulty Sliding Roof ECU – If the ECU has stopped communicating, it might need to be reset, reprogrammed, or replaced.
- Hydraulic or Mechanical Jam – The system may be detecting resistance, preventing the top from moving further. Inspect for any obstructions or binding.
- Initialization Needed – Some Lexus retractable tops need to be re-initialized after a battery disconnect or electrical repair.
Recommended Troubleshooting Steps:
- Check for Other Trouble Codes – Use a scan tool capable of reading Lexus body control module (BCM) codes to see if additional faults are stored.
- Perform a Battery Voltage Check – Ensure your battery is fully charged and connections are secure.
- Manually Inspect the Roof Mechanism – Look for debris, misalignment, or mechanical binding that could be preventing movement.
- Try the Roof Reset Procedure – Some Lexus models allow a reset by holding the roof button in a specific sequence (refer to the owner’s manual or service documentation).
- Check the Sliding Roof ECU Wiring – Look for loose or damaged wiring leading to the ECU.
If the issue persists, a professional scan tool (such as Techstream) may be needed to diagnose deeper system faults. Let us know what you find, and we can help guide you further!
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