Check Engine Light - BACK AGAIN x3!

That's why if you have even a modicum of understanding of modern powertrains you want a cheap scantool in your vehicle so you can determine if the cause of a light could cause further damage or not.

One feature I like is flashing check engine lights for misfires that may damage the cat.

 

Called the dealership today to find out if they figured out the engine/trac lights issue and have my truck ready for pickup. There was no answer so left a voicemail. Now that I'm back in town I will need a loaner vehicle if it is not done. They've had it for 5 full days.

 

Welcome home. What kind of service department doesn’t have someone to answer the phone during business hours?

Sorry this has been such a saga for you. Let us know when you hear something.

 

^When I read you pulled over and had it towed, rather than delivering it personally to the dealership I cringed, only to read on and see this. I'd rather keep both as far from my truck as possible. Giving them a simultaneous a pre-dawn shot at it was a recipe for disaster.

Last trip in for warranty work, my Mustang came back with a nice solid door ding.
I was too furious to address it with the dealership. Called the dent wizard and had it fixed myself.

Sorry to see it and and say it, but the only person that actually cares about your truck is you.
I hate blemmed rims too..

 

Just to name another:
Toyota of Cleveland
Cleveland, TN

Three for three, on three different days. All looking to schedule service.
Messages left -3
Calls returned -0

Welcome to America.

 

Thanks all. For the foreseeable future I will be rolling around in a 2018 Toyota Camry SE. All I was told is they will keep me posted on my truck. I saw it sitting outside their maintenance bay so guess they are waiting on Toyota to tell them how to fix it.

 

Got a call this morning that my truck is ready. Not quite sure they have a correct diagnosis but just like I thought they're trying to blame the mods I've done to the truck for check engine light and trac off light. They said the tech thinks my audio amp is causing a draw that is setting off the instrument cluster. Makes no sense since the amp has it's own dedicated power line. I have aftermarket audio equipment in my other vehicles and they don't have a CEL and I know many other people on this forum have audio installs in their Tacoma as well.

 

That should be easy to confirm, pull the fuse or disconnect the amp.

BTW, knowing you upgraded the audio / changed the load on the stock electrical system would have been helpful to know in the first post of this thread. I assumed everything on the truck was stock other than your wheels. With as many sensors, computers and diagnostics running in these new trucks it doesnt take much of a change in the load to throw a false indication. We've had guys throw codes from changing interior bulbs to LEDs.

 

The audio system has been installed for over a year. Why would the instrument lights come on now? I think it's a misdiagnosis, if audio system installs caused CEL and trac off lights then there would be a lot of Tacomas on this forum with the same issue.

The list of modifications I've done is in my signature below. Anyone can see everything I've done to my truck.

 

Could be a chafed wire causing a ground over time, poor connection that makes and breaks, all kinds of reasons your truck could be having faults others do not have.

As for seeing what mods you have in your signature, anyone using the mobile TW app like me will not see your signature.

 

Bad connection/chafed wire causing intermittent short would also have unmistakable effects on his audio system. As for non-stock loading of the electrical system, he said he used a direct connection to the battery. Holy hell a lot of winch users are in trouble then!
I agree pulling the amp fuse should put all thoughts of that being the cause to rest. Did these so called techs do that? Seems pretty straight forward.
BtW I know about the LED bulbs causing issues.

 

They diagnosed it as a wheel speed sensor the first time it was brought in. So if they misdiagnosed it the first time doesn't seem unreasonable they did again. I've had no issues with the sound system. I still have to pick up the truck and we'll see if I get a better explanation in person. I assume they expect me to pay since they deemed it not warranty related.

 

It all depends on the installation, I've seen good electrical work by non electricians and poor work done by electrical engineers.

 

Did it throw the same code this time as the diagnosed wheel sensor did the first time?

 

I have no clue, all I heard from the service advisor last week was that they opened a case with Toyota to help them fix it. No one has ever explained all the tests that were done. When I go pick up the truck maybe the tech will be around to explain all the tests he did and why it was diagnosed as a wheel speed sensor the first time. The truck was driven less than 10 miles between the first time it was brought in and the 2nd time.

 

Need to know the specific codes thrown to make a determination, different combinations of codes can trigger the same lights you see on the cluster.

 

Post #23 has what it was diagnosed as the first time it was brought in -- P050031 vehicle speed sensor circuit. I'll post the work order invoice from this 2nd time around when I get the truck later today.

 

If it's the same code then they should consider changing out the speed sensor and do continuity checks of the sensor circuit. All they did last time according to your invoice was reset to see if it returned.

P050031 does indicate a speed sensor not sending signal to the ECM.

http://zatonevkredit.ru/repair_manuals/raw_content/RM1000000011G1L.xml

If it's a different code that includes cascading faults then consider isolating the amp to see if it returns.

 

From the 3G Tacoma service manual. Hell, I could easily use techstream (and my Tactrix cable) as described in the procedure to at least narrow it down.

 

Wheel sensor(s) > harness > skid control ECU > harness > Comb meter display > harness > ECM.

OP, have you had ANY issues with the speed displayed in the combination meter or the actual speedometer?

You could also check the speed indicated against a GPS..