Disabling Bluelink on the 2026 Santa Cruz
**obligatory not responsible for damage to your vehicle**
So i was successful in my attempt to disable bluelink on my 2026 Santa Cruz SEL. It was actually super easy. Pull a fuse to the DCU. I removed my bluelink account from my trucklet then turned it off to pull the fuse. Totally reversible for the dealership. The infotainment system no longer recognizes the modem. The truck complains about me removing myself as the owner but everything works. Carplay, gps, etc. Took an hour drive and no codes either.
I bought a 7 day sub to the Hyundai service manual portal to trace the wiring harness and to investigate how ingrained bluelink is. turns out not that much. Hyundai engineers threw us a bone by having the DCU completely separated from the rest of the system. The antennas are about as hard as you can get to get to so for me at least this was the easiest way to accomplish my goal.
I worked through it with Claude to double check my work and findings. I know, I know AI bad but i needed someone (or something) to double check me. I had it do a technical write up for anyone interested in the bluelink system on the santa cruz with my findings. You can read it below if it interests you.
tldr: Remove bluelink account from trucklet, turn off, pull fuse f18, throw in glove box. Its just a really nice vehicle now.
Its not about stopping all your data from getting out. That's almost impossible. but you can plug a few holes. And if you like bluelink by all means keep using it. I just didn't like it personally.
*i have 7 days left with access to the Hyundai service site. if you need anything and don't wanna pay 40 bucks let me know.
----technical write up follows-----
2022-2026 Hyundai Santa Cruz — LTE Telemetry Disconnect Technical Reference
This technical reference was generated by AI (Claude) based on diagrams and schematics from the 2026 Hyundai Santa Cruz ETM (Electrical Troubleshooting Manual) obtained via hyundaitechinfo.com. All schematic references correspond to the NX4A OB platform.
Vehicle Connectivity Architecture Overview
The Santa Cruz has two separate LTE antenna systems that feed into a dedicated cellular modem called the DCU (Data Connectivity Unit). These LTE feeds are electrically isolated from the AM/FM, GPS, and SXM antenna feeds, which go to the CCNC head unit.
Antenna Routing
Source: ETM Schematic SD969-4 — A/V & Navigation (CCNC/AMP) System (4)
Roof Sharkfin Antenna (P.195) — 4 coax feeds:
| Pin | Color | Signal | Destination | Connector Path |
|---|---|---|---|---|
| 1 | Black | AM/FM1 | CCNC Head Unit | ANT-A → MM31 → MM21 → M11-AN1 |
| 2 | Blue | Dual GNSS | CCNC Head Unit | ANT-A → MM31 → MM21 → M11-AN2 |
| 3 | Red | SXM | CCNC Head Unit | ANT-A → MM31 → MM21 → M11-AN2 |
| 4 | Yellow | CCS1 (LTE1) | DCU | ANT-A → MM31 → MM21 → M19-AN1 |
Crash Pad Antenna (P.91) — 1 coax feed:
| Pin | Signal | Destination | Connector |
|---|---|---|---|
| 1 | CCS2 (LTE2) | DCU | ANT-C2 → M19-AN2 |
AM/FM, Dual GNSS, and SXM terminate at the CCNC head unit (M11-AN1, M11-AN2). CCS1 and CCS2 terminate exclusively at the DCU (M19-AN1, M19-AN2). The two systems are completely separate at the module level.
DCU (Data Connectivity Unit)
Source: ETM Schematic SD955-1 — Data Connectivity Unit (DCU) System (1)
Location: Center of cowl cross bar, behind the main crash pad
Connectors:
| Connector | Description | Pins |
|---|---|---|
| M19 | Main connector | 32-pin black |
| M19-E | Ethernet to CCU | 2-pin |
| M19-AN1 | CCS1 coax (LTE1 from sharkfin) | 1-pin |
| M19-AN2 | CCS2 coax (LTE2 from crash pad antenna) | 1-pin |
Key circuit details from M19 (32-pin):
| Pin | Function | Wire |
|---|---|---|
| 16 | Ground | 0.3B |
| 17 | B+ Input | 0.3W |
| 23 | DCU Reset (from CCU M06 pin 4) | 0.22Gr |
| 19 | CCU Wake Up (to CCU M06 pin 15) | 0.22P |
Network connections:
- Ethernet (M19-E) to CCU (M06-E) CAN bus connections: None.
The DCU has no connections to any CAN bus (C-CAN, E-CAN, P-CAN, B1-CAN, B2-CAN, M-CAN). It communicates exclusively over Ethernet to the CCU. It cannot interact with engine, transmission, braking, ADAS, or any other vehicle control system.
Power supply: Dedicated "HOT AT ALL TIMES" circuit through fuse F18. The DCU can transmit with the vehicle off.
CCU (Central Communication Unit)
Source: ETM Schematic SD200-24/25 — Central Communication Unit (CCU) (1)(2)
Location: Center of cowl cross bar, adjacent to DCU
The CCU is the vehicle's central network gateway. It connects to all six CAN buses and the Ethernet backbone. It is documented here to illustrate that the DCU is a leaf node on the network, not a gateway.
CCU CAN bus connections (M06, 36-pin):
| Pins | Bus |
|---|---|
| 7, 25 | C-CAN |
| 5, 23 | E-CAN |
| 24, 6 | P-CAN |
| 2, 20 | B1-CAN |
| 19, 1 | B2-CAN |
| 10, 28 | M-CAN |
CCU Ethernet connections (M06-E, 12-pin):
| Pins | Connection |
|---|---|
| 10, 9 | ETH_CCNC (Head Unit, M11-E) |
| 8, 7 | ETH_DCU (DCU, M19-E) |
| 12, 11 | ETH_CLU (Cluster Unit) |
| 3, 4 | ETH_ADAS (ADAS Parking Unit, F40) |
Disconnecting the DCU removes one Ethernet endpoint from the CCU. The CCU continues to function as the vehicle network gateway for all remaining modules.
Fuse F18 — Wireless DCU
Source: ETM Fuse & Relay Information SD100-1/SD100-2
Location: PDC (Powernet Domain Controller) fuse box, passenger compartment, driver's side, behind the lower crash pad panel
| Fuse | Name | Amps | Circuit Protected |
|---|---|---|---|
| F18 | wireless DCU | 7.5A | DCU |
F18 is a dedicated fuse. No other circuit or module shares it. Removing F18 cuts power exclusively to the DCU.
Disconnect Procedure
Steps:
- Open the fuse cover on the driver's side lower dash panel.
- Locate fuse F18 (wireless DCU, 7.5A) in the PDC fuse box.
- Pull fuse F18.
- Close the fuse cover.
Verification
Navigate to: Infotainment System → Bluelink → Modem Information
Expected result with F18 removed:
| Field | Value |
|---|---|
| USIM | (blank) |
| IMEI | (blank) |
| Network Carrier | (blank) |
| Network Status | (blank) |
| Signal Strength | 0 dBm |
Systems Unaffected
The following systems have no dependency on the DCU and are unaffected by removing F18:
- CCNC Head Unit (CarPlay, Android Auto, Bluetooth, WiFi, AM/FM, SXM, GPS Navigation)
- All audio (speakers, amplifier)
- Cluster unit
- All ADAS systems (FCA, LKA, BSM, RCCA, HDA, SCC, parking sensors)
- Engine management
- Transmission
- Braking (ABS, ESC, EPB)
- Steering (MDPS)
- Lighting
- Power windows, locks, seats
- Climate control
Systems Affected
- Bluelink remote services (remote start, lock/unlock, vehicle locate via app)
- SOS / eCall (emergency cellular calling)
- OTA software updates
- All cellular data transmission to/from the vehicle
Reversibility
Reinstall fuse F18 to restore full DCU functionality. No reprogramming or dealer visit required.
ETM Reference Index
| Schematic | Title | Relevant Content |
|---|---|---|
| SD969-4 | A/V & Navigation (CCNC/AMP) System (4) | Antenna routing — AM/FM, GNSS, SXM, CCS1, CCS2 |
| SD955-1 | Data Connectivity Unit (DCU) System (1) | DCU connections, power, antenna inputs |
| SD200-24 | Central Communication Unit (CCU) (1) | CCU power, wake-up, D-CAN |
| SD200-25 | Central Communication Unit (CCU) (2) | CCU CAN buses, Ethernet backbone |
| SD100-1 | Fuse & Relay Information (1) | PDC fuse box layout |
| SD100-2 | Fuse & Relay Information (2) | PDC fuse table — F18 entry |
Applicability
- 2022-2026 Hyundai Santa Cruz (NX4A OB) — all trims and engine variants
- The Hyundai Tucson (NX4, 2022-2026) shares the same platform and likely has a similar architecture, but should be independently verified via ETM before applying this procedure