2022-2023 Audi e-tron GT / RS e-tron GT Software Update & AC Sensor TSB 91VT

Audi has issued Technical Service Bulletin (TSB) 91VT UPDATE, a Customer Satisfaction Package (NVLW), to address several potential issues in 2022-2023 Audi e-tron GT and RS e-tron GT vehicles. This proactive update aims to prevent various conditions related to the air conditioning system, gearbox locking mechanism, and high-voltage charging functionality. Owners of affected vehicles should have this Audi e-tron GT software update 91VT performed by an authorized Audi dealer.

Symptoms

This 91VT UPDATE addresses the following potential conditions that owners might experience:

• Air Conditioning Malfunction (Criteria K1): Air conditioning pressure/temperature sensors (G395, G826, G827) may fail, leading to a non-functional air conditioning system. This issue affects Audi vehicles from a certain production period.
• Gearbox Lock Error (Criteria 01): After turning off the engine by pushing the start/stop button, the gearbox lock could possibly not be in the end position. This can result in the lock no longer releasing and a warning message on the instrument cluster stating, "gearbox error, max 120km/h, go to workshop."
• High-Voltage Charging Issues (Criteria 02): Vehicles may display an unauthorized "Turtle LED" for a short time when the KL15 (ignition) is off, indicating the high-voltage (HV) system is in the state "not ready to drive." This can also result in charging duration loops at less than 100% or charging aborts (indicated by a red LED), making fast charging no longer possible.
• Combined Issues (Criteria 03): This applies to vehicles experiencing both the gearbox lock error (Criteria 01) and the high-voltage charging issues (Criteria 02).

Important Warnings and Advisories

Audi has provided several critical warnings and instructions for technicians and owners regarding this update:

• Vehicle Eligibility Verification: The ELSA Campaign/Action Information screen is the only valid source for verifying vehicle eligibility for this update. Other systems are not valid and may result in non-payment of a claim. The status in ELSA must show "open" on the day of repair.
• Refrigerant Handling During Inspection: During the inspection of AC sensors, technicians are advised, "Do not recover the refrigerant charge during the inspection section." The refrigerant pressure/temperature sensors do not require removal for inspection.
• Refrigerant Handling During Replacement: If replacement is necessary, there is a "Danger of frostbite due to refrigerant coming out under pressure. Frostbite on the skin and other parts of the body is possible." Technicians must wear safety gloves and protective eyewear. It is critical to evacuate or drain refrigerant and open the refrigerant circuit immediately. If more than 10 minutes elapse after extracting or draining the refrigerant and the refrigerant circuit has not been opened, the refrigerant must be extracted or drained again due to pressure developing from evaporation.
• Software Update Connection: The VAS Diagnostics Interface "MUST ONLY be connected to the tester with a USB cable." Performing a software update using a Bluetooth or Wi-Fi connection significantly increases the risk of losing connection, which could result in damage to the control module. Audi will deny requests for additional time or parts if the GFF log shows the update was performed via Bluetooth or WiFi.
• Radiator Fan Safety: "WARNING Radiator Fan(s) may cycle ON high speed during the Update Process! There is a serious risk that personal injury may result if contact is made with spinning fan blades. Keep hands and all objects away from Radiator Fan(s) during Update Process!"
• Battery Charger Use: Technicians must use a battery charger (such as the VAS5908) set to a charging voltage of 14.8V during the software update. It is crucial, "DO NOT change any settings that will damage the charger or the vehicle." An insufficient charging voltage can damage one or more control units. After the software update has been performed, the battery charger must be restored to the original voltage value.
• High-Voltage System Error During Update: If the "High-voltage charging active - precondition not met" error message appears after performing the software update, the high-voltage system must be deactivated, the update performed again, and then reactivated.
• Software Update Failure: If the software update fails for any reason, ODIS feedback must be sent prior to further diagnosis. This ensures the failure/error is reported. Failure to do so may result in non-payment of consequential requests for additional time or parts.
• TAC Case: If the error message "Configuration on control unit 0046 – convenience system central module could not be performed" is displayed during the flashing process, technicians are instructed, "DO NOT create a TAC case as this is not required." They should select option #1 to cancel the configuration and continue with the software update.
• Customer Notification: Dealers are required to "Inform your customer in writing by recording on the Repair Order any and all work that was conducted on the vehicle, including any and all updates completed under this Update."
• Dealer Inventory: The procedure must be performed on applicable vehicles in dealer inventory prior to sale.

Technical Background

This customer satisfaction package, identified as 91VT UPDATE, has been proactively released to address specific conditions identified in certain production periods of Audi e-tron GT and RS e-tron GT vehicles. The issues stem from potential failures in air conditioning pressure/temperature sensors (G395, G826, G827), a gearbox lock mechanism that may not reach its correct end position, and various anomalies within the high-voltage system affecting charging capabilities. The remedies involve either hardware replacement for sensors or software updates for relevant control modules to ensure proper vehicle function and prevent these conditions from manifesting.

Repair Procedure Summary

The repair procedure for the Audi e-tron GT software update 91VT varies based on the specific criteria applicable to the vehicle. All procedures require checking vehicle eligibility in ELSA and ensuring all open campaigns are performed, starting with the oldest first.

AC Sensor Inspection and Replacement (Criteria K1)

For vehicles exhibiting air conditioning issues, the procedure involves inspecting the G395, G826, and G827 refrigerant pressure/temperature sensors. These sensors are located in various positions, as shown in the document's figures (e.g., sensor 1 near the top left, sensor 2 below it, sensor 3 on the right side of the engine bay). Technicians will look for a green dot on all three sensors. If a green dot is present on all sensors, no replacement is needed. If a green dot is NOT present, the production date of the sensor is checked (e.g., as shown in the document's figure of a sensor labeled with a production date like '340204' indicating week 34 of 2020). Sensors produced on or before calendar week 31 of 2021 require replacement. The replacement process involves evacuating the refrigerant, replacing the affected sensor(s) (part number 4M0-959-603-E), and recharging the A/C system with R1234yf refrigerant. Reassembly involves specific torque specifications: wheel bolts to 160 Nm, luggage compartment light bracket bolt to 3 Nm, luggage compartment bolts to 8 Nm, and wiper arm nuts to 30 Nm.

Software Update Preparation

Before any software update, several critical steps must be followed:

1. Diagnostic Scan: Perform a full diagnostic scan using GFF (Guided Fault Finding) and send the diagnostic protocol online. The diagnostic session should be saved so it can be restored later if needed.
2. Bus Sleep: After the diagnostic scan, perform a bus sleep for at least five minutes. This involves disconnecting the 12V charger and diagnostic interface, closing all doors, the hood, and the rear lid, locking the vehicle, and waiting for all interior lighting to turn off.
3. Power Management: Switch off all vehicle consumers (air conditioning, heater blower motor, lights, heated seats, etc.). Reconnect the battery charger (e.g., VAS5908) and ensure the voltage is above 14V, as displayed on the ODIS tester (e.g., a screen capture shows '14.29 V').
4. ODIS and Tester Setup: Ensure the ODIS software is completely up to date. The screen saver and power saving settings on the tester must be off. The VAS Diagnostic Tester must be plugged in using the supplied power adapters, and the diagnostic head must be connected to the ODIS tester via a USB cable. The selector lever must be moved to 'P'.
5. Battery Charger Pre-programming: For the VAS5908 battery charger, switch it off and back on. Ensure its display has switched off before restarting. Operate it in charging mode and set it to a charging voltage of 14.8 Volt (access code 6161 may be necessary or activate DIAG+ mode). Do not change any other settings. Customer presets should be documented as a best practice before any update.
6. Service Action 93P9: Service Action 93P9 must be performed before completing this software update.

Software Update Process

The software update is performed using the "FLASH" operating mode with a CAN communication path. Technicians select "SVM – Code Input" and enter the appropriate SVM code:

• Criteria 01 and 02: Use SVM code SWVGTA001.
• Criteria 03: Use SVM code 91VTA396.

Follow the on-screen prompts. If a "High-voltage charging active - precondition not met" error message appears after performing the software update, the high-voltage system must be deactivated, the update performed again, and then reactivated. If a "Configuration on control unit 0046 – convenience system central module could not be performed" error occurs during flashing, technicians should select option #1 to cancel the configuration and continue the update without creating a TAC case.

Post-Update Checks

After the software update is complete:

1. Instrument Cluster: Check the displays in the instrument cluster; there must not be any fault messages or warning lamps.
2. Bus Sleep: Perform another bus sleep for at least five minutes with the 12V charger disconnected.
3. Parking Brake Calibration: If warnings or messages in relation to the position of the parking brake are present, perform the test plan "0003 – calibrate parking brake" via guided functions (diagnostic address 0003, as shown in a screen capture of the Guided Functions menu). Confirm that the parking brake position warning/message is no longer present.
4. Battery Charger Reset: Restore the battery charger to its original voltage value.
5. Diagnostic Log: Ensure the diagnostic log is sent to GFF Paperless after completion.

Required Tools and Parts

Performing the 91VT UPDATE may require the following special tools and parts:

Special Tools

• Battery Tester/Charger: VAS5908 (or equivalent charger with a current rating of at least 90A)
• Diagnostic Tester: VAS6150X/VAS6160X (or equivalent)
• Socket - 24mm: T40284 (or equivalent)
• Engine Bung Set: VAS6122 (or equivalent)
• R1234yf Air Conditioning Service Unit: ROB1234YFX or VAS581005
• Removal Wedge: T40233 (or equivalent)
• Scraper Set: VAS6845
• Omega Clip Tool: T40280 (or equivalent)
• Puller - Windshield Wiper: T40394

Parts

• AC Pressure Sensor: Part Number 4M0-959-603-E (up to 3 units)
• Oil Refrigerant: Part Number G-052-535-M2 (up to 1.6 ml)
• R1234yf Refrigerant: (up to 98g, locally sourced)

Warranty Information

This is a customer satisfaction package, and the work performed under TSB 91VT UPDATE is covered under the New Vehicle Limited Warranty. The Service Number for this action is 91VT, with Damage Code 0099 and Parts Vendor Code 002. The Claim Type is 7 10 for sold vehicles and 7 90 for unsold vehicles. Causal indicators include "Mark labor as causal" (for vehicles not assigned K1), "Mark labor as causal if all SENSORS are OK," or "Mark any SENSOR* as causal if any sensors are NOT OK." Dealers must ensure the SVM Process is completed entirely for the database to receive update confirmation, as warranty claims may be denied without this confirmation. Owners should note that "Do not claim wash/loaner under this action."

Labor operations and time units vary by criteria:

Labor Op	Time Units	Description
2706 89 50	SEE ELSA	Battery charge
0151 00 40	100	Software update (includes preliminary and follow-up work)
9310 83 00	SEE ELSA	Disable HV system voltage deactivate and activate
0150 00 60	Time stated on diagnostic protocol	GFF/Guided functions
4405 19 51	SEE ELSA	1 Wheel remove+reinstall
6644 19 50	SEE ELSA	Cowl panel trim remove+reinstall
7007 19 50	SEE ELSA	Storage compartment remove+reinstall
8709 01 99	15	Check 3 pressure sensors
8703 17 00	SEE ELSA	Refrigerant drain+fill
8709 20 50	SEE ELSA	3 Pressure switch remove+reinstall (use if all sensors replaced)
8709 19 50	SEE ELSA	Pressure switch remove+reinstall (if G395 replaced)
8709 19 51	SEE ELSA	Pressure switch remove+reinstall (if G826 replaced)
8709 19 52	SEE ELSA	Pressure switch remove+reinstall (if G827 replaced)

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Source: NHTSA ID: 11009268