Dtc 1330 & vsc off/vsc trac lights (1 Viewer)

[alatlc]

Background first, and then a few questions. Sorry in advance for the length, but there is diagnostic history at two separate shops that helps paint the picture, and I know you guys like details.

New to me 2005 with 71k. Drove it for a week with no warning lights, and then took it back to the dealer (non-Toyota dealer) to get the trailer wiring socket/plug replaced (PO apparently backed over something and tore it up). No evidence of prior rewiring of the truck. Dealer gets the trailer wiring redone by his guy, and as I drive off the lot after picking it up, the VSC OFF and VCS TRAC lights come on. The lights don't come on until you put the truck in gear and actually start to drive (they come on as soon as the truck moves a foot or two). No alarms or other lights. Truck still drives fine. So the dealer takes it to his mechanic who says the truck needs a new yaw rate sensor. Dealer doesn't give me a code number and I wasn't present when they scanned the truck. They want to put a used yaw rate sensor in it, which makes me a little nervous, so I tell them I'm going to get another opinion and will get back to them.

I then took the truck to a local shop that does Toyota/Lexus work (they did basic maintenance work on my first LC and my Sequoia, so I used to trust these guys). They pull the codes with me standing there and get a DTC 1336 - Zero Point Recalibration of Deceleration Sensor Undone. They tell me they can likely recalibrate and all will be well, so I make an appointment and bring the truck back the next day. After they have the truck for a day I get a call saying that the yaw rate and decel sensors are working fine, but the truck needs a new steering angle sensor. They also tell me that they think the trailer hookup rewiring would not have caused this problem. I get the "I can't guarantee it, but a new steering angle sensor will MOST LIKELY fix your problem." They then quote me $1,015 to get that work done. I ask about the price of the sensor, and the guy tells me he doesn't know but that the labor is $188 of the total, so the sensor is the rest. I pay him for his diagnostic time and leave, and being diligent (and suspicious of a $1000 "most likely" fix), I call two Toyota dealers to get a retail price on a steering angle sensor - $384.80 at both places. I also notice, after I leave, that the paperwork they gave me shows a code of C1330, which I can't find in the diagnostic manual.

So now I have two different diagnoses, the last from a shop that is either marking up a part 100+% or has innocently misquoted the repair cost. I'm thinking about taking the truck to a local Toyota dealer for another diagnosis. So with that background, here are my questions:

1. In your experience, could the trailer rewiring cause the VSC OFF and VSC TRAC lights to illuminate? I know I bought a used truck, but it eems like a pretty big coincidence that the lights popped on right after the wiring work.

2. I've read a previous thread where someone had a similar problem after disconnecting their trailer wiring, and the lights went off after the wiring was reconnected. Should I try to disconnect the trailer wiring harness to see of the lights go out? I don't want to cause any more problems.

3. Is there a C1330 DTC?

Thanks in advance and sorry for the length.

 

[EdsCruisin]

Process of elimination - disconnect the trailer harnesss and see what happens. But first, what did they fix on the trailer circuit? The stock converter is known to be a POS and some on this board have reported other symptoms from that failure. To be sure you may need to access the converter and disconnect there.

Second is go to a local auto parts shop and have the manager read the codes for you. They don't fix anything, so they will be the most honest, let you see the code on the reader and show you the code in their manual.

Good luck.

 

[re_guderian]

My 2000 doesn't show a C1330 either. But lay down 50 bones at Harbor Freight for a code reader. Good thing to have in your glove box...

 

[wildsmith]

You can read the code by shorting pins TC & E1 of the diagnostics connector in the engine bay, turn the ignition on and count the ABS or VSC warning light flashes - 4 second pause between codes, flash flash quickly for a digit, short pause, flash flash quickly for next digit, gives you the last two digits which is all you need as you already know which sub-system you're looking at. This tells you as much as the code reader will.

The original symptoms are consistant with 'DTC 1336 - Zero Point Recalibration of Deceleration Sensor Undone' but getting to that state requires specific actions with the OEM hand controller or some hocus pocus with the diagnostics connector and ignition on/off so many times, not something that should happen by accident / component failure.

I can't see a 1330 code either.

 

[alatlc]

Wildsmith, when you mentioned "OEM hand controller" and "ignition on/off so many times" it made me think of something I hadn't before. One thing I forgot to mention in my original post is that a hi-tech locksmith came out to program a new master key for me, and one thing I saw him doing (in addition to hooking up his programming computer to the truck - it looked like a mega code reader) was turning the ignition on and off to, I assume, program or test the new key. Any way what he was doing could have caused the lights to come on?

Sorry, but I'm not technically proficient enough to know what "specific actions with the OEM hand controller" you are talking about, but this jogged my memory.

 

[wildsmith]

The 1336 code would trigger as soon as the truck moved after the deceleration and yaw sensor calibration zero point was cleared so if it didn't happen after the locksmith did his thing that didn't cause it (not likely anyway). To expand a bit, the ABS ECU reads voltages from those two sensors that change as the truck moves and the ECU needs to know what the 'rest' values are i.e. dead level and not moving to make sense of the active values. That's the 'zero point' values the code refers to. There's an action to clear the values which should be followed by the action to set them. If you clear them and don't set them you get this code. Normaly replacement of one of those sensors is the only reason you'd reset/set the calibration.

If fiddling with the diagnostics connector doesn't appeal to you then get a code reader as re_guderian suggested but it does sound like you need a way of getting the code you can 100% trust.

 

[NMuzj100]

I doubt that trailer wiring issues would cause the warning lights to activate. But the short drive to the trailer wiring shop could allow a previously cleared but not fixed or properly fixed code to reset. Usually the code does not set the CEL on the first detected error but has some sort of logic (zero point values out of range >4 times in 12 starts [hypothetical example]) to keep from generating false errors.

Get the scan gauge. Everyone with them seems happy. The cheap code reader pays for itself very quick.

 

[alatlc]

Thanks for all of the input, guys. I will definitely get a code reader. In the meantime, the dealer I bought the truck from took it to a local Toyota dealer to get it diagnosed. He says they were able to recalibrate everything. Once I get a look at the paperwork I'll post a more definitive answer to close out this thread.

 

[alatlc]

Just to close the loop, after two independent Toyota shops claimed I needed two different types of new sensors (yaw rate and steering angle), one of the local Toyota dealers diagnosed a 1336 code and recalibrated the decel sensor on my truck for all of $50. Score one for the dealer service departments.

 

[wildsmith]

That's good you got it sorted. Have to wonder why/how someone cleared the calibration in the first place when the tow electrics were done.