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12K views 40 replies 9 participants last post by  thedill 
#1 ·
I'm getting tired of paying dealer to rotate tires and reprogram TPMS sensors. I know the procedures to follow, but was wondering how strong a magnet I need. From the looks of GM's J-41760 tool, the magnet is a pretty common looking horseshoe type. I have a source identified for horseshoe magnets, and was wondering if I should get one rated at 22 lbs. of pull, or should I go with the 30 lb. one---or something with even less strength. Thanks in advance for any advice.
 
#2 ·
Someone said that radio shack has magnets that work. I purchased a set for about $2.50. There are 5 round magnets that stack on each other. They are about 1 1/8" dia. with a 3/8" hole in the center. Unfortunately I have not tried them yet. On second thought, there is no time like the present. I'll go try them.

So much for that idea. THEY DON"T WORK. :mad: Guess I'll have to find something stronger.
 
#3 ·
They worked fine for me. I was also able to use a magnetic broom from Home Depot. You know one of those things for picking up debris in the driveway.

The magnets don't have to be supper strong but you have to be able to get it on the side of the valve stem.

The ones from Radio Shack are a package of 5 small donut magnets that work like a charm.

Ranger if they didn't work for you something is wrong with the sensors. I had one that was stuck and I had to tap on it while the magnets were on it.

Actually I think they went to RF sensors in 02 or 03 so the magnet reset may not work for either one of you.
 
#4 ·
Nothing wrong with the sensors. I watched discount tire reprogram them when they did the road force balance and rotation. The radio shack magnets did not slip all the way down over the stems. Maybe I need to bore the hole out a little bit if I can do that without cracking them. I'll give that a try tomorrow.
 
#5 ·
All the sensors are RF; reprogramming procedures may have changed in later models, but my 2002 is reprogrammed using the magnet at each valve steam as specified in the reprogramming procedures. The magnet forces/stimulates the sensor to transmit its identification code. Once the receiver learns the first sensor ID, all previously stored codes are erased from the receiver's memory. I believe the receiver is the same one that receives the key fob transmitter's signals for locking/unlocking.
 
#7 ·
You're the first one I've heard say they don't fit. You did take the caps off right? If you can get a relatively strong magnet that you can fit on the length of the valve stem, that will work. Assuming that this is the proper procedure for your car.


The radio shack magnets are ceramic and don't drill well. I'll have to find something better. They do work very well for magnetizing/demagnetizing screwdrivers though. :thumbsup:
 
#8 ·
They fit over the caps just fine, but stop at the mounting nut. I can get the horn to beep by simultaneously pressing the lock/unlock buttons, but nothing happens when I put the magnets on. That is why I suspect either they are not going down far enough or are too weak.
 
#9 ·
No they stop at the nut. They don't go beyond that at all. Are you using all 5? I don't think they have to be very strong Ranger.

Try this, I think you have 60 seconds to train each sensor so while the magnets are on there take the handle of a screw driver or something of the sort and give it a few whacks.

If the horn beeps you're in business. If that doesn't work I have no idea what to say.
 
#11 ·
You don't have to use a certain number of them, and you don't have to surround the valve stem.
You can lay it on the flat portion of the wheel on the inside (if you can reach through the hole) and rub it on the inner diameter of the wheel near the sensor.
All you need is to get the magnet in proximity of the sensor.
We sometimes use the magnets on the back of our bolt trays. The ones with the round 4 inch magnets on them.
You just hold it over the sensor until the horn chirps.
If it won't program, try moving to the next sensor, if it programs easily then you likely have a bad sensor.
Of course you'll have to start over later once it's fixed but this way you can figure out if any are bad.
 
#14 ·
This is all good info. That's how I got to tapping mine. The first one set like a dream and I couldn't get the second one to go. I grabbed a screw driver out of the trunk, set the first one, went to the second and after I was firmly holding the magnets in place I gave the valve stem a couple good whacks then a continuous tapping and sure enough she went.


You don't have to use a certain number of them, and you don't have to surround the valve stem.
You can lay it on the flat portion of the wheel on the inside (if you can reach through the hole) and rub it on the inner diameter of the wheel near the sensor.
All you need is to get the magnet in proximity of the sensor.
We sometimes use the magnets on the back of our bolt trays. The ones with the round 4 inch magnets on them.
You just hold it over the sensor until the horn chirps.
If it won't program, try moving to the next sensor, if it programs easily then you likely have a bad sensor.
Of course you'll have to start over later once it's fixed but this way you can figure out if any are bad.
 
#12 ·
Well, last night when I left work it was 8 degrees outside. After starting the car I got the check tire pressure message. Pressures were at 23. I fugured it was due to the cold temps as last time I checked them they were around 30. I tried reseting them again this morning and got a beep from the LF only. Just went back and tried it again. NOTHING, but now I get a SEVICE TIRE PRESSURE MONITORS message and the following DTCs. Guess it's off to the "Doctor".

B0429 - Temperature Control #3 Rear Circuit Range/Performance (Unrelated)
U1016 - Loss of Communications with PCM (Related/Unrelated ???)
C0750 - Tire Pressure Monitor (TPM) system sensor not transmitting
C0755 - Tire Pressure Monitor (TPM) system sensor not transmitting
C0760 - Tire Pressure Monitor (TPM) system sensor not transmitting
C0765 - Tire Pressure Monitor (TPM) system sensor not transmitting
 
#13 ·
Ranger. That's normal man I had that also. The system is in a state of limbo because once the first sensor is reset the computer awaits the other three. That's why you're seeing that error.

Don't worry I'm sure it's an easy fix. Did you have to tap on that to get it to go?

Also, it takes a few seconds for the sensor to send the signal. How long are you waiting? One of mine took like 10 or 15 seconds to trip. Maybe even longer.

I don't think these two are related but I've had the later also. Are they current or history.
B0429 - Temperature Control #3 Rear Circuit Range/Performance (Unrelated)
U1016 - Loss of Communications with PCM (Related/Unrelated ???)
 
#15 ·
Well, the first one worked after tapping on it. Couldn't wack it too hard as it is in an ackward position. Second one would not beep. I waited for a while and figured if it did not respond by that time, it was not going to. I can understand the state of limbo thing, but if it does not register in 60 seconds it is supposed to go back to normal I thought. Even after turning the ket of and then back on, I still get the message. She has a "Doctors" appointment Wed. morning. I'll let them figure it out since she is still under warranty, especially with the PCM code. I don't like that one.
 
#16 ·
It doesn't go back to normal it just exits programming mode. They'll fix it. I'll bet that second sensor is bad.

I can understand the state of limbo thing, but if it does not register in 60 seconds it is supposed to go back to normal I thought.
 
#18 ·
I ran the codes on the way in to work this afternoon and guess what. B0429 (current) & U1016 (history) are present. The mechanic that told me he could not find them (not sure what method he was using, Tech II I suspect), is the same mechanic that took 3 tries to fix the seat heater on the SLS last year. I'm starting to see a pattern here.
 
#19 ·
I know that feeling. I do think you have a bad sensor though. This reset thing is really very simple when everything is working right.
 
#20 ·
Update:
Replaced 2 sensors. Advisor said they where damaged, likely by Discount Tire when they did the RFB. He warrantied them anyway. I am not sure I buy that because I was in the shop at Discount and watched everthing he did. If he did something to damage them, it was not obvious to me, plus I watched him reset the sensors and they worked fine for a few months. Now I'm just hoping that the other two are ok. Guess I'll have to try those Radio Shack magnets again tomorrow. Maybe I can break the other two sensors. :)

As for the B0429 code, I finally convinced the mechanic that is was real and after some futher searching he found it. He showed me a printout obviously from the CD manual and as best as I could tell he was talking about it being a passenger side air mix door actuator just slightly out of synch, but since I am not actually having any problems with it, I told them I would monitor it for a while (still have 3 years on the warranty) rather than come back for the replacement.
 
#21 ·
Thanks for the update. They do go bad though. It may be nobodies fault. I think they have batteries in them that die. Someone said 3 - 5 years was the life expectancy.
 
#22 ·
B0429 means the actuator is going bad.
If you check, usually the temperature discharge out of the vents to the rear seat won't work right.
You won't notice it up front.
I don't even give it a second look, if I see a B0429 I replace the actuator.
It's really easy.

It's also easy to crack the sensors if you don't clock them right when you mount the tire.
It's hard to explain but you have to run the tire on the rim and make sure it goes over the sensor last, if it goes over in the middle it can crack the sensor and you are done.
Easier to do than most people think.
 
#23 ·
Thanks Bill.
Funny you mention this becasue the mechanic said that it had nothing to do with the rear seat blower temp, but was the passenger side which bleeds to a vent "under the front seat". :hmm: That makes no sense at all simply based on the code definition. If that were the case, why have a rear blower? Strange thing is the other night I was on my way home at midnight and for some reason reached back to see if the rear blower was on. It was and the air coming out was ice cold, while the dash vents were hot and engine was normal operating tempurature. I'm gonna check it again, but from what you are saying (and I trust you a lot more than this guy), I think I may be taking it back next week. I may even request that it be given to another mechanic. I realy do not trust this guy. Each time I have any dealing with him, he proves himself more and more incompetent. Thanks for the input. I really appreciate it.
 
#24 ·
That actuator is actually pretty complicated.
It's two actuators in one.
There are two mechanisms built into it and it's usually the one for the back air vent that goes bad.
Nobody notices it because it's in the back seat.
Just take it in and complain about the air discharge in the back, when they see that complaint and check codes they should replace that actuator.
Make sure you don't leave your porn in the glove box ;)
It has to be removed to replace the actuator.
I guess maybe if you do leave some porn in there maybe the guy will take better care of your car? Who knows, I guess it depends on the guy?
 
#28 ·
I don't think they need calibration. And they don't report immediately. It takes a while for the sensors to report the new pressures. Do yourself a favor though and get a decent pressure gauge.

In addition if the tires have been moved around you'll be adding and removing air form the wrong tires. That's what happened to me.
 
#29 ·
well the thing was everything was ok, tires look ok except when its really cold it will notify me to check tire pressure

and RR reports as 22 psi low until it warms up to i think 25 psi ok well today i added air to all of them, about (3 psi each) and now they all show ridiculously high numbers
 
#30 ·
Hmm well that's one annoying thing about the system with regular air. extreme cold and heat make the sensor tell you about it. they're just doing they're job so I ignore it and more on.

The numbers you're seeing I have a feeling are coming from ice or something in the sensor. I'm not sure though. I would get a gauge, reset the sensor positions and check the tires with a gauge to ensure they're correct. then ignore the system until warmer months and see what happens.
 
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