The brake light relays location depends on the type of car. Many car manufactures place the relay next to the main cabin fuse box.
We found the relay check lamp was the problem after replacement of vehicles stop light switch.
The stop lamp relay on a Vauxhall Vectra is typically located in the fuse box, which is usually found in the engine compartment. Depending on the model year, you may also find a secondary fuse box inside the vehicle, often near the driver's side dashboard. To identify the specific relay, consult the vehicle's owner's manual for a diagram of the fuse box layout.
I found three. One with the radio, one with the wipers, and one with the stop lamp relay.
NO relay just fuse.
The fog lamp relay is on under the hood and mounted to the driver side wheel well. It's to the left of the washer fluid resevoir, you'll see the wires. The fog lamp relay plugs in on the top.
The fog lamp relay is in the Power Distribution Box ( which is " live " ) in your engine compartment ( on the drivers side ) The relay is in the 2nd row from the drivers side and is the 2nd relay from the front of the box ( one of the small relays )
The photocell would typically control a relay. The power to the lamp would go to one pole of the relay and the lamp to the other. The common wire and ground would go directly to the lamp. The relay would be normally open and would close when the light energy on the photocell decreased to an amount that would trigger a circuit to close the relay.
According to the owners manual - relay 203 is the Trailer Tow Backup Lamp Relay
The three relays starting from the left are fuel pump relay, horn relay and fog lamp relay (if equipped).
The CHMSL (Center High Mount Stop Lamp) relay on a 1993 GMC Sonoma is typically located in the underhood fuse and relay box. This box is usually found near the driver's side of the engine compartment, close to the battery. You may need to consult the owner's manual for a specific layout and identification of the relay.
Fuel pump relay, horn relay, fog lamp relay and if there is a fourth relay, power door locks.
The fog lamp relay on a Dodge Challenger is typically located in the fuse box under the hood. To find it, open the hood and look for the fuse box, which is usually near the battery. The exact position of the fog lamp relay can vary by model year, so it's best to consult the owner's manual for the specific location and diagram.