Side lights wont turn off!

[confused.com]

Hello everyone. I hope this is in the correct forum, and hasn't been discussed before! I did a search but came up with nothing!

My girlfriend has a Toyota Yaris Saloon year 2000, and tonight the side lights (front and rear) wouldn't turn off. I thought it must be either - a relay (if one was even needed for the sidelights, which I doubted) or the light switch itself.

I pulled relays out one by one, nothing. I then pulled out fuses. When I removed the 50A one under the dash, the side lights (front and rear) went out. Here is where it gets very strange though. The light switch still worked as normal with the fuse removed (first position side lights came on, second dip, pull/push main beam), BUT when the light switch is in the OFF position, no dash lights, radio, or digital display work!

When turning the light switch to the first position, they all come back on!

So is there another relay hidden somewhere, or have missed something very obvious?? This seems like a very bizarre fault...

Any help or suggestions with this would be very much appreciated!

Best wishes and thanks in advance!!!

[CTScott]

Does your Yaris have the daytime running lights (where the headlights are on, when the engine is running, with the headlight switch off)?

If not, then there are no relays in circuit with the side lights. The switch directly controls them (and in that case is likely bad).

If you do have DRLs, then there are two relays in circuit with the lights - The Tail Light relay (attached to top right side of the under-dash fuse panel) and the daytime running light relay (a module located under the top of the dash to the right side of the instrument cluster).

[confused.com]

Thanks for your quick reply! No it doesn't have DRL's, but the bit that is confusing me is - when the 50A fuse is pulled from under the dash, and the lights go out, the switch then seems to operate perfectly, albeit at the cost of the radio dash lights and display!

[CTScott]

Try putting the fuse back in and just pulling the connector off the headlight switch.

Is the 50A fuse that you are pulling labeled as the AM1 fuse?

[confused.com]

I cant remember what it the label is, but there is only one 50A fuse. Pulling the connector off of the light switch/stalk??

[CTScott]

I cant remember what it the label is, but there is only one 50A fuse. Pulling the connector off of the light switch/stalk??

Remove the lower steering column cover to get at the connector. There are two screws that you get to by turning the steering wheel half way in each direction, and then a third by the tilt mechanism. Then, with the 50A fuse back in, unplug the connector from the base of the headlight switch to see if the lights stay on or off.

[confused.com]

Thank you very much for all of your help with this, and your quick replies! I will try this later!

[confused.com]

Hi again. I unplugged the connector, and put the fuse back in, and surprisingly (to me anyway) the lights were on again! :( So I am now thinking alarm/ECU related fault?

It certainly is a strange fault, and maybe not the cheap and quick fix I was hoping for!! :/

[CTScott]

Hi again. I unplugged the connector, and put the fuse back in, and surprisingly (to me anyway) the lights were on again! :( So I am now thinking alarm/ECU related fault?

It certainly is a strange fault, and maybe not the cheap and quick fix I was hoping for!! :/

Do you have a factory or aftermarket alarm?

[confused.com]

Yes there is one fitted. Not sure what make or model though, or whether it is an alarm fitted by Toyota? Do you think that's the only plausible explanation now?

[CTScott]

Yes there is one fitted. Not sure what make or model though, or whether it is an alarm fitted by Toyota? Do you think that's the only plausible explanation now?

I believe so. I would try to find it and pull its harness (or give it a good slap) to see if the issue goes away. It is likely that it has a relay where the contacts have stuck.

[confused.com]

Thank you so much for all your great advice!! I know where it is located so will have a look later. When you say a a relay stuck, you mean internally in the alarm, or externally??

[CTScott]

Thank you so much for all your great advice!! I know where it is located so will have a look later. When you say a a relay stuck, you mean internally in the alarm, or externally??

Internally. They typically contain a bunch of small relays for controlling the flashing of the lights, honking of the horn, etc. The relay contacts can stick due to electrical arcing, during the switching process. If that happens, giving the relay a good slap will usually free the stuck contact. Once it happens it is likely to happen again, so you want to eventually replace the bad relay.

[mudnuri]

I have the opposite issue. I can't get the side markers in front of the doors or on the side of the headlamp assemblies to turn on. All fuses are good. Checked both boxes. Checked all bulbs. I would really like a wiring diagram or at least tell me what fuse is supposed to be offering power to these lights. Wife's '09 Yaris is almost invisible from the side at night. Must get it fixed right away. Hope this is related enough for this thread as I have searched and searched for this issue on here and can not find how or where to start a new thread.