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Check - Trac Off - VSC Trac Lights On

I have had my 2002 Toyota 4 Runner SR5 for a few years now and it’s been a very reliable machine. The Check - Trac Off and VSC Trac lights used to come on maybe every three fill ups but I would reset by disconnecting the battery. But now they are coming on within each fill up and within the first 100 miles of driving. So I had this Mobil Mechanic come by a couple of times and tell me that his little gizmo says that it is the Catalytic converter. Of course I’m skeptical because the Trac and VSC lights are on as well as the Check light. I’m thinking that maybe he has a cheapo little gizmo and that maybe it has something to do with the brake system.
What do you think?

You may have more than one issue. VSC problems can occur if the wheel speed sensors are out of whack, which can indeed be related to the braking system. The size of the ECM/DTC code reading gizmo has no relation to it’s functionality. Most of the code readers , even the aftermarket version, should be able to determine DTC’s associated with the cat. But the VSC codes often require a Toyota scan tool to determine the actual cause. Find someone with a Toyota scan tool or equivalent and ask them to check for VSC codes and verify all of the wheel speed sensors are working.

Back when they were coming on regularly, they were coming on for a reason. That you reset them, just delayed when they would come on again. You should have had it looked at immediately when they first came on. It looks like you are looking for the easy and cheapest way out when an earlier service might have been just that; cheaper than it might be now. Take it in for service now. This is part of your ABs and traction control system and can cause more problems then they help if the aren’t working correctly.

When checking faults with a Techstream (Toyota scan tool) and the “Check engine” light is on, the fault in the ABS module is usually C1201 Engine control module fault/malfunction.

Focus on the engine faults. Be sure to verify that the downsteam oxygen sensors are working, if one is dead catalytic converter faults are invalid.

I guess I should run it over to Toyota for the check but I know that they charge way more than a good station would but then again a good station might charge for more than I need. Catch 22 but I don’t really have much of a choice. I guess it’s spend the money time.
Thanks to all of you for advising me on this issue. I’ll try to get back after another check on the system.
The thing is I can’t afford to buy a newer vehicle so I can only keep putting money into the 4 Runner which is getting on in years. I’ve put a couple of thousand into it already with timing belt, water pump, gaskets, bushings, shocks, tires, brakes with new rotors, and more. It runs like a clock even when the lights are on. I just didn’t think that the lights really were an indication that I need to get it serviced but just that some of the traction features are no longer functioning. I mean what if I just continue to ignore the lights?

I mean what if I just continue to ignore the lights?

Your truck is producing more pollution than some others. A failing catalytic converter or oxygen sensor are emission control concerns.

If you ask around you’ll likely find many independent shops specializing in Asian cars that own the Toyota scan tool.

All I can add to this discussion is that my “Trac-Off” and VSC Trac" lights came on a bunch when it turned out the battery was dying. It still started the car but after a while it didn’t. This was on a 2005 Lexus is300, which has lots of Toyota stuff in it. I finally bought a new battery and never saw the lights again.

I understand you’re a cheapskate. Well, if you are, then you have to do some work. Search on Google for “trac-Off” and VSC and Toyota and forum and see if you can turn up some ideas. If you don’t want to do the homework, shine up your credit card.

What hasn’t been mentioned is that, on many cars, when the CEL lights up, the VSC and Traction Control lights will also light up.

Here is the scenario as I see it:
The vehicle’s OBD system has detected a problem that could be as simple as a loose gas cap, or perhaps the need for spark plug replacement, or perhaps a bad purge valve in the evaporative emissions system, or it could be one of scores of more complex problems, but the bottom line is that when the OBD system detects a problem that causes the engine or the emissions systems to run less-than-optimally, features such as Cruise Control, VSC, and Traction Control are automatically disabled. In other words, the VSC & Trac lights are lit up as a result of the CEL being lit up.

Although the OP didn’t mention it, I would be willing to bet a cup of coffee that the Cruise Control is not currently functioning.

Diagnose and fix the underlying problem which is causing the CEL to light up, and those other lights will turn themselves off, and the Cruise Control will function again.

The Trac system is turned off when there is a malfunction with the engine control system. That is why the vsc and Trac lights are on. A cat is highly possible on this car.