Illumination lighting out, green wire is now grounded?

[visualfxengineer]

I am hoping to get some guidance on an issue that I have been struggling with resolving.

The illumination for switches, stereo buttons and parking indicator on the console are out.

I was worried it was the ECM based on some threads here, but no code at kragen and everything else appears to work correctly that I have tested.

2017 sr5.

Observations:
Fuse for panel and tail fuse, no short there.
No error code when plugged into ODBII
Tail Lights work
DRL work when car on
Turn indicators and turn signals work.
Dash instrument cluster (speedo+guages) has light
Dash dimmer works on ONLY instrument cluster
Stereo works
Trip Info works as well
Interior dome and map lights work.

I had thought maybe i messed up the dimmer circuit, but the dial still works on cluster so I am trying to track down the source of it. It appears to be just an issue with the button lights next to the stereo, shift indicator on console and switches.

This wire was feeding my aux switch lights when I had a tap on it at the switch. It was working previously. I have a wire soldered to the green wire on the de-icer button. this wire feeds my illumination for my compressor and aux light switches.

I hooked up the multimeter to check if anything might be grounded or shorted. I discovered that the green wire going into the de-icer/rear wiper is getting continuity to ground. When the car is on if i test the de-icer green wire, the meter will change audible tone along with the dimmer adjustments.

So green is grounded. All the posts I read say that it is dash light positive and that grey is ground. However this green wire out of the wiper/de-icer button is not positive, but grounded. Additionally that grey wire I tested and it is not grounded. I may have also swiched the grey and green cables when trying to get the dimmer working. In hindsight, it was just fine with only illumination and not dimming. I was on a roll and should have quit while i was still making positive progress.

Perhaps there is a way to remove the other end of the de-icer/wiper witch, eliminate that as a cause.

Any help is appreciated as I am not making any progress here. I am concerned of what may happen down the road if that positive cable continues showing as ground. Everything besides the illumination seems to be working, but I am not sure if this issue will remain isolated to just illumination.

Hopefully I posted in the correct category. It looks like the illumination threads are mostly inn the Gen specific sections of the forum.

Thank you.

 

[KP Texan]

At the risk of using a wiring diagram from 2010 and it being wrong for yours, the only light green wire I see in that circuit is supposed to go to ground in order to actuate the coil for the de-icer relay. Could that be the wire you are reading from? That being said, it doesn't look like it goes to the switch, but rather the A/C amplifier assembly. Again, yours may be different since it's a 2017 so maybe someone can chime in with with an updated wiring diagram.

 

[visualfxengineer]

Thank you for the response and diagram!

I may be describing it wrong. In Socal not much use for these buttons. i believe that the red one i highlighted is the de-icer. that is the cable i tapped the green and grey off of.


Edit: resized image for sanity

 

[KP Texan]

Thank you for the response and diagram!

I may be describing it wrong. In Socal not much use for these buttons. i believe that the red one i highlighted is the de-icer. that is the cable i tapped the green and grey off of.


Edit: resized image for sanity

Interesting. Yeah, it doesn't look like my wiring diagram colors jive with what you have.

Edit: Nevermind what I wrote is not correct. I'll have to look at it again.

 

[visualfxengineer]

Interesting. Yeah, it doesn't look like my wiring diagram colors jive with what you have.

Edit: Nevermind what I wrote is not correct. I'll have to look at it again.

I really appreciate the time and effort. Thank you

 

[KP Texan]

Old Red is guiding you in the right direction here.

My apologies, I was looking at the wrong diagram and when I saw the LED on there I was thinking it was for illumination when, in fact, that switch also has a light when it's actuated. The 2010 wiring diagram actually shows the same thing as the one Old Red posted.

Interested to hear the outcome of this, and I hope you get it fixed!

 

[Superjet]

Green at the switch is powered directly off Panel fuse, 7.5a

You are seeing ground on a circuit that is not energized yet still hooked up to light bulbs, resistance of a light bulb is usually only 4ohms.

 

[visualfxengineer]

I may have located one of the issues. In this picture you will see 2 arrows indicating a snapped wire. You will also see a t-tap in a square. It is my thought that this brown/green wire that is t-tap caused a sever in that green wire.

So I will fix that now. Wonder if this has anything to do with my horn doesn't honk whn I use the remote.

However I am curious, i bought this new from a Toyota dealership. Why are there t-taps in the kick panel area. This feels like it was done after the fact.

Follow up question, how does the star wiring pass the muster?

Anyone know what these t-taps go to? There is also a snipped relay hiding behind there as well. I'd like to clean this up as I fix that wire.

 

[flyrv9]

Looks like you have some dealer installed or aftermarket installed wire mods for perhaps an alarm system (like the Karr alarm) that they may have not told you about. I'd go back an ask as it definitely is not factory. T-tap splices are probably the worst type of splice and will eventually cause problems anyway. I suggest you get rid of them and depending on what you discover you really have going on there - either remove them or replace with a descent splice.

 

[visualfxengineer]

I have the Karr sticker. They said they disabled it when I bought it. However if i open the door handles inside with the car locked from the keyless entry, it will sound an alarm. Based on the blinking of the immobilizer light when locked, it lines up with having a basic oem alarm, no remote start and no glass break tilt sensor. unfortunately the dealer is in on the wrong side of the state and too much time has expired to go harass them now.

 

[flyrv9]

Big difference between disable and uninstall (return to original). I think the majority of your issues are related to this wiring. Either way I suggest it be removed, all connections repaired. Then you can see where you stand as far as what works and what doesn't. A diagram of all the Karr alarm wiring and connections would help. Perhaps the dealer can help there - depends on who did the wiring though. There have been a few threads here by members with pre-installed Karr alarms. When they refused to buy - the dealer just disabled it. Then time goes by and problems surface. One member challenged this and ended up getting the dealer to completely remove the wiring.

 

[Superjet]

I would turn lights on and meter panel fuse for 12v on both sides of the fuse on the metal terminals on top. If there is power on one side but not on the other replace it.

 

[ToyotaBE]

Hi,

I currently have the same issues on a second hand Lexus i bought a few weeks ago. 3 days ago i noticed that I have the exact same issue as you, although everything seems to be stock in my car.

Did you ever fix the issue, and if so, what fixed it. At least i know what to look for then.