Help with Toyata Yaris 2005 1.4 Diesel P1520 Error Code

[YayYaris]

Hey Guys

Recently brought a 2005 Yaris T-Spirit 1.4 Deisel with 74,000 on clock. It's my first car and suffice to say I'm well excited.

That being said I've done a full service (had prior mechanical experience) and I've made sure everything should be shipshape.

• New fuel filter (blueprint)
• New air filter (blueprint)
• New Oil filter (you guessed it, blueprint)
• 540 Fully Synthetic Oil 
• Removed EGR valve, cleaned it. 

Although I've been having trouble with the an error code P1520.

I detected the code using a bluetooth OBD scanner and I cleared it but it still returns. I've had no luck googling and I was wondering whether any of you guys could help?

 

[Devon Aygo]

P1520

Stop Light Switch Circuit Malfunction

DTC No.	DTC Detection Conditions	Trouble Areas
P1520	Conditions (a), (b) and (c) continue for 5.0 seconds or more: (a) Ignition switch on (IG) (b) Brake pedal depressed (c) STP signal OFF when ST1 signal OFF (The MIL is illuminated and a DTC is set when the same malfunction is detected on 2 consecutive trips* *: One trip is counted when the ignition switch is turned from off to on (IG) and back to off)	Short in stop light switch signal circuit Stop light switch ECM