2021 Audi R8 Electrical Switch & Relay Parts

Engine:
5.2L V10

The 2021 Audi R8 has 11 electrical switch & relay parts with verified fitment on this page — 6 part types and 8 brands, covering the 5.2L V10 engine. Each part includes a manufacturer part number and application notes.

On the 2021 Audi R8, the switch and relay system covers the switches, relays and flashers that route power to everything the driver touches. 8 parts of the 11 listed are Oil Pressure Sender / Switch (5 parts), Horn Relay (2 parts) and A/C Refrigerant Pressure Switch (1 part). The other 3 part types cover the remaining 3 parts.

A/C Refrigerant Pressure Switch

Brand Part Number Markets Notes Buy
FOUR SEASONS 37427
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
Pressure Switch
Fitment notes — FOUR SEASONS 37427
Pressure Switch
Transducer
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This table covers the pressure switches on the A/C circuit. Typical signs include a function that works intermittently, or a click without the accessory coming on. Inspect the connector behind the switch; heat-damaged terminals will kill the new part too.

Brake Light Switch

Brand Part Number Markets Notes Buy
WELLS 1S10938
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
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This table covers the pedal-mounted switch that turns on the brake lamps. Typical signs include a function that works intermittently, or a click without the accessory coming on. Inspect the connector behind the switch; heat-damaged terminals will kill the new part too.

Horn Relay

Brand Part Number Markets Notes Buy
HELLA 965453801
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
5-pin connector
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WELLS 1R2303
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
Mounting Hardware Included: No
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This table covers the relays that control the Horn circuit. Typical signs include a click with no action, or a circuit that works only when you swap in a known-good relay. Swap with an identical relay in the fuse box before buying — it is the fastest test there is.

Ignition Starter Switch

Brand Part Number Markets Notes Buy
WELLS 1S17872
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
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This table covers the ignition switches that feed the starter circuit. Typical signs include a function that works intermittently, or a click without the accessory coming on. Inspect the connector behind the switch; heat-damaged terminals will kill the new part too.

Multi-Function Relay

Brand Part Number Markets Notes Buy
BOSCH 0986AH0080
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
Multi-Purpose Relay
Fitment notes — BOSCH 0986AH0080
Multi-Purpose Relay
70 Ampswith 4 Blade Connectorwith Marking # 1KO951253A
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This table covers the relays that control the Multi-Function circuit. Typical signs include a click with no action, or a circuit that works only when you swap in a known-good relay. Swap with an identical relay in the fuse box before buying — it is the fastest test there is.

Oil Pressure Sender / Switch

Economy

Brand Part Number Markets Notes Buy
WALKER PRODUCTS 2561078
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
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Standard Replacement

Brand Part Number Markets Notes Buy
BECK/ARNLEY Popular 2011987
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
with Light
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ROSTRA 501405
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
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STANDARD MOTOR PRODUCTS PS488
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
Black
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WELLS 1S10850
🇺🇸 US 🇨🇦 CA 🇲🇽 MX
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This table covers the senders and switches that report oil pressure to the gauge or lamp. Typical signs include a lamp that stays on, or a gauge that never moves. Confirm power and ground at the connector before replacing the sender or switch.

Buying Electrical Switch & Relay Parts for a 2021 Audi R8

On this vehicle, the switch and relay system covers the switches, relays and flashers that route power to everything the driver touches.

  • Confirm you have the 5.2L V10 engine — every part on this page is matched to it.
  • Read the notes on each row for position, trim and spec qualifiers before you order.
  • Where labor overlaps, inspect the connector terminals behind any failed switch — heat damage there will kill the new part too.
  • Cross-reference the manufacturer part number against your old part or a service-manual listing.

Start with the largest groups on this page: Oil Pressure Sender / Switch and Horn Relay .

Frequently Asked Questions

How many electrical switch & relay parts fit the 2021 Audi R8?

Our catalog currently lists 11 electrical switch & relay parts for the 2021 Audi R8 across 6 subcategories and 8 brands, covering the 5.2L V10 engine. Each part is matched to the engine(s) it fits.

What are the signs of electrical switch & relay problems on a 2021 Audi R8?

Common symptoms include accessories that work intermittently, a click without action, or one function dead while its fuse tests fine. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.

What should I replace at the same time?

Where labor overlaps, inspect the connector terminals behind any failed switch — heat damage there will kill the new part too.

What do the market flags (US, CA, MX) on each part mean?

They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 2021 Audi R8 was originally sold in the US, the safest choice is a part marked for the US market.

How do I make sure a part fits my 2021 Audi R8?

Every part on this page is matched to the 5.2L V10 engine. Then swap a suspect relay with an identical known-good one from the fuse box before buying — it is the fastest diagnostic there is. The notes column carries position and trim qualifiers where they apply.

Other Parts for the 2021 Audi R8

Electrical Switch & Relay Parts for Other Audi R8 Years

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Manufacturer names, model designations and part numbers are used for identification and fitment reference only. AutoFactsDB is an independent catalog and is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer displayed on this page.