Dash Dimmer Switch Not Working

As you have almost certainly seen my posts on this I will not go into details here, but fitting heated mirrors is fairly easy to accomplish. An extra power socket could also easily be fitted, but I agree particularly on the flagship model in the UK both should have been standard equipment.

John (Britprius)

 

My dimmer was working fine until I had the dash apart last night to add LEDs in the arm rest. Today It works at full brightness, turn it down a little only the radio dims, turn down more the dash dims and the MFD screen dims but flickers in brightness, go all the way down the MFD screen is ok but no lights on the dash as expected. Anyone have a wiring diagram or suggestions?

 

Did you disconnect any of the connectors to the switches and the dimmer rheostat when you dismantled the dashboard? Check the connections, sounds like something is loose.

 

Did not disconnect anything but will look when I get home. Wonder if the pins are loose or a wire got pinched.

 

here is whats going on when I move the dimmer. Reseated the plug and no change. Should I check fuses? My light behind the shifter knob died too.


I can make a better video if needed.

 

Tested all my fuses with a light up fuse tester and all good. Decided to order a replacement dimmer at this point. Noticed my steering wheel lights died too but the buttons work.

 

I have a similar issue with mine. Started driving my car and noticed I had no display on the dash nor displaying fuel consumption. Dimmer will not work at all and cannot see speedometer.
A video on YouTube shows to unplug a small connection in the battery compartment for 30 secs and plug again.

I am yet to try that.

 

Fixed by replacing an interior fuse named "Panel" 7.5a.

 

I just had recall No. 18V-684 (Hybrid System Software Update) performed on my 2010 Prius by my local dealership. When I picked up my car, the dash lights were only about half as bright as they used to be. Also, the dimmer switch for the dash lights, which had worked whether the headlights were on or off, now only works with the headlights on.

The dealership service manager told me that everything is working according to Toyota specs. How frustrating! I have had this car for 10+ years. I KNOW how it worked. The service write-up person then searched and found a fix for the dimness of the lights...seems there is a range of -2 to +2, with the default being 0. They were able to change my display to +2, so at least it is as bright as it used to be fully dialed up. But the dimmer switch still only works with the headlights on.

The service write-up person said he would submit the issue to Toyota and see if they have a solution so that the dimmer switch will again work with the headlights off.

 

I just bought my son's 06 Prius from him and the dimmer switch connector was also disconnected. I searched high and low looking for a solution to this problem but found absolutely nothing. Your post was a tremendous help and had the information I couldn't find anywhere else. I popped the vent and reconnected the connector just as you said; WORKING!!! THANKS, THANKS, THANKS. Great post!!! YEARS after your posts, it is still helping people and it literally took just a minute, just like you said.