TR6 Brake warning light & oil pressure light stay on

[Gerry M]

I have a 1974 TR6. My brake warning light and oil pressure light come on when ignition is turned on (motor not running). When motor is started both lights stay on and continue to stay on while driving. Oil pressure gauge shows oil pressure is good and brakes work. I've checked wiring on oil pressure switch (3 prong) and that looks correct. Any suggestions?

 

[number6]

Had a similar problem on my spitfire. Brake warning light on. Fault was in the PDWA valve body. Brake light is connected in series parallel with the the oil
warning light. Reason is the shuttle in the valve body has shifted due to a brake fluid issue. Have you had any brake issues or bled the system recently?
Cure is to reset the shuttle by bleeding the correct side so the pressure moves shuttle back to center. Usually you will find a good explanation in a TR-6 manual.
My description is a bare bones explanation.

 

[TR3driver]

I'd try disconnecting the lead for the oil lamp at the oil pressure switch. If that makes it go out, the switch is bad.

IIRC, on a 74 TR6, the oil and PDWA lamps are in series, so the oil light goes out if the PDWA switch is closed.