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Service procedures 2026 firmware

Read or Write Shunt Data

Gen3/tasks/PROC_HVP_X_WRITE-SHUNT-BAR-RES

What this task does

This routine provides the ability to read or write the shunt data from/to the High Voltage Controller (HVC).

Vehicle & firmware coverage

Open a version to see its description, requirements, and input definitions. Hardware configuration and live vehicle checks also determine availability.

Model 3 / Y AMD · Firmware 2026.32.3
Vehicle coverage
2024+ Model 3, 2025+ Model Y, Model Y, Pre-2024 Model 3
Supported connection
Local connection
Vehicle state
Stationary · Parked; Stationary · Neutral
Gateway diagnostic level
Service, DiagLinkActive, Factory

Procedure notes

Writing the wrong shunt data may cause the vehicle to falsely trigger the pyro disconnect and/or prevent pack contactor closure.

Task inputs (3)

Operation

OPERATION · String

Select wether to read or write the shunt data.

Firmware default: READ

Options: READ, WRITE

Shunt Bar Resistance (nOhm)

SHUNT_BAR_RESISTANCE · Int

If WRITE operation selected, enter the the shunt bar resistance (in nOhm) found on the part sticker.

Firmware default: Not specified

Shunt Part Number

SHUNT_PART_NUMBER · String

If WRITE selected, choose the correct shunt part number as seen on the part sticker.

Firmware default: NONE

Options: 1078835-00-G, 1078835-00-H, 1078835-01-H, 1588177-00-A, 1588177-00-B, 1994650-00-B, 2084224-00-A, NONE

Model 3 / Y Intel · Firmware 2026.32.7
Vehicle coverage
Model Y, Pre-2024 Model 3
Supported connection
Local connection
Vehicle state
Stationary · Parked; Stationary · Neutral
Gateway diagnostic level
Service, DiagLinkActive, Factory

Procedure notes

Writing the wrong shunt data may cause the vehicle to falsely trigger the pyro disconnect and/or prevent pack contactor closure.

Task inputs (3)

Operation

OPERATION · String

Select wether to read or write the shunt data.

Firmware default: READ

Options: READ, WRITE

Shunt Bar Resistance (nOhm)

SHUNT_BAR_RESISTANCE · Int

If WRITE operation selected, enter the the shunt bar resistance (in nOhm) found on the part sticker.

Firmware default: Not specified

Shunt Part Number

SHUNT_PART_NUMBER · String

If WRITE selected, choose the correct shunt part number as seen on the part sticker.

Firmware default: NONE

Options: 1078835-00-G, 1078835-00-H, 1078835-01-H, 1588177-00-A, 1588177-00-B, 1994650-00-B, 2084224-00-A, NONE

Model S / X (2021+) AMD · Firmware 2026.20.6.1
Vehicle coverage
2021+ Model S, 2021+ Model X
Supported connection
Local connection
Vehicle state
Stationary · Parked; Stationary · Neutral
Gateway diagnostic level
Service, DiagLinkActive, Factory

Procedure notes

Writing the wrong shunt data may cause the vehicle to falsely trigger the pyro disconnect and/or prevent pack contactor closure.

Task inputs (3)

Operation

OPERATION · String

Select wether to read or write the shunt data.

Firmware default: READ

Options: READ, WRITE

Shunt Bar Resistance (nOhm)

SHUNT_BAR_RESISTANCE · Int

If WRITE operation selected, enter the the shunt bar resistance (in nOhm) found on the part sticker.

Firmware default: Not specified

Shunt Part Number

SHUNT_PART_NUMBER · String

If WRITE selected, choose the correct shunt part number as seen on the part sticker.

Firmware default: NONE

Options: 1078835-00-G, 1078835-00-H, 1078835-01-H, 1994650-00-B, 2084224-00-A, NONE

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Self-tests

Charge Port Interlock Loop (CPIL) Self Test

This routine tests the Charge Port Interlock Loop (CPIL) is working properly, ensuring the charge port HV connection at the HV battery is made.

TEST-SELF_HVP_X_CP-INTERLOCK

Model 3 / Y
Service procedures

Force HVIL Current Source On

Forces the High Voltage Processor (HVP) High Voltage Interlock Loop (HVIL) current source to be on for the specified duration in seconds. When the routine completes, the HVIL current source is no longer being forced on. To end the routine early, perform a Gateway (GTW) reboot through scroll wheel reset."

PROC_HVP_X_FORCE-HVIL-ON

Model 3 / Y Model S / X (2021+)
Self-tests

HVP and PCS Enable Line Interface Test

Diagnoses an issue between the High Voltage Processor (HVP) and Power Conversion System (PCS). Enables wiring interface by toggling the DCDC, CHG, and PCS enable lines between the HVP and PCS. If the PCS, HVP, and/or Battery Management System (BMS) are absent, all three lines will report a failure.

TEST-SELF_HVP_X_PCS-INTERFACE

Model 3 / Y Model S / X (2021+)
Communication checks

HVP CAN Communication Test

This routine will test if the High Voltage Processor (HVP) is communicating over CAN. Note that if the High Voltage Battery Management System (HVBMS) is MIA, this routine may falsely fail since the HVBMS forwards all HVS components status' to the Gateway.

PING-TP_HVP

Model 3 / Y Model S / X (2021+)