ABS and Wheel Slip lights come on when parking lights are on

I have a 2012 Double Cab 4x4 TRD sport. When I turn the parking lights and/or headlights on, the ABS and Wheel Slip lights come on. I can turn the ignition and parking lights off, restart the engine and everything looks normal until I turn the parking/headlights on again. I have not had a chance to read the error codes yet. Has anyone seen this before or have any ideas why this happens only with the parking and headlights on?

 

Do you have aftermarket LED brake/tail lights in the rear?

 

@Dm93 I have the DEPO brake/tail lights but have had these for several years without any issues.

 

I mean being it only happens when you turn the tail lights on I'm thinking something is backfeeding voltage into the brake light circuit, if that's the case it could be a faulty bulb or bad ground.

 

Agree. The brake light circuit feeds into the abs and vsc modules, so a faulty component in that circuit could create all sorts of issues with those modules. Haven’t looked at my taco bulbs, but most applications use a common bulb for stop tail. No issues for std bulbs, but led likely uses a common pcb and can therefore cross contaminate the stop circuit.

 

Put back the stock lights and see if that fixes it.

 

Ok, so I noticed something a bit strange today. I left work earlier today so I did not need my lights on but after I got on the road I turned the lights on and off several times and neither the ABS nor the wheel slip light came on. I used my brakes several times and still no indicator lights. When I got home I backed into the driveway and tried a few things. I observed that the two indicator lights only come on when the ignition is on, the parking lights are turned on, and only after lifting my foot off of the brake pedal while in park. I'm leaning towards a bad speed sensor because this is related to both the wheel slip detection and the ABS. I just don't get how the parking lights figure into this. I'll try disconnecting the tail lights (the stock lights as well as the aftermarket DEPOs are both LED). I'll also see what code is being thrown and try to track the problem down that way. Thanks for the input!

 

Sorry but the tail light doesn’t tie into that assumption. Problem only occurs when tail light is on, so need to find something common to that circuit. Abs and wheel sensors have no connection to the tail circuit.

fyi, the slip light tells you the vehicle is slipping and vsc is stepping in to stop it, not an indication that one wheel is spinning. Blip the gas in the snow on the driveway from a stop. Wheels spin, no light. Come around the corner and blip, you fishtail, then light goes on.

 

Update: So the 'problem' seems to have gone away on its own and I cannot duplicate it. Oh well.