All the Roadster electrical relays are located in, or adjacent to, the SAM unit. The relays within the SAM are non-serviceable but are unlikely to fail over the life of the car. All the relays within the SAM unit are common to fortwos and Roadsters but some of them are not used, depending on the car.
The relays located within the SAM unit on the main I/O board are as follows:
| Relay Code | Relay Function | Make | Comments |
|---|---|---|---|
| K1 | Rear window and wing mirror heated elements. | Tyco V23076-A3001-C132 | Wing mirrors - optional at factory. |
| K2 | Electric soft top. | Fujitsu FBR512ND10-W1 | Dual relay for up and down. |
| K3 | Starter motor. | Tyco V23076-A3001-C132 | |
| K4 | Fuel pump. | Fujitsu FBR51ND10-W1 | |
| K5 | Exhaust catalytic system pre-heater pump. | Tyco V23076-A3001-X019 | |
| K6 | Full beam headlights. | Tyco V23072-C1061-A408 | |
| K7 | Engine master. | Tyco V23076-A3001-C132 | Injection valves, ignition coils etc. |
| K8 | Dipped beam headlights. | Tyco V23072-C1061-A408 | |
| K9 | SE drive (gear change system). | Tyco V23076-A3001-C132 | |
| K10 | Front wipers. | Fujitsu FBR51ND10-W1 | Also requires relay K26 on Roadsters only. |
| K11 | Fan blower, electric windows, heated seats | Tyco V23076-A3001-C132 | Heated seats - optional at factory. This relay switches when key is in position 1. |
| K12 | Front & rear side lights, interior console backlights. | Fujitsu FBR51ND10-W1 | |
| K13 | Rear wiper. | Fujitsu FBR51ND10-W1 | Not applicable on Roadsters. |
The relays on the microprocessor unit contained within the SAM are as follows:
| Relay Code | Relay Function | Make | Comments |
|---|---|---|---|
| K820 | Horn, intercooler (or chargecooler) fan | NAiS ACT512 B02 | Chargecooler - only applicable on Brabus Roadsters |
| K830 | Central Locking | NAiS ACT512 B02 | |
| K840 | Rear boot lid solenoid | Omron G8N-1S |
The number of accessible relays will depend on the functions fitted to your Roadster at the factory. All Roadsters will be equipped with the wiper system relay as a minimum:
The complete relay arrangement is as follows:
| Relay Code | Relay Function | Comments |
|---|---|---|
| K26 | Wiper system. | Fitted to all Roadsters (pink base frame). |
| K52 | Fog lights. | Optional (blue base frame). |
| N25/1 | Left heated seat module. | Combined relay and controller. |
| N25/2 | Right heated seat module. | Combined relay and controller. |
