TPMS - True or B*** S***
 

Hi All,

I need your help to determine if my local Dodge dealer is telling the truth or is making up an excuse. Here is the scenario:

2010 SXT 34000Km - Factory 17" wheels with TPMS fitted

After reading a few other threads in this forum on the subject of TPMS and winter wheels, I purchased a brand new set of steel wheels and winter tires for the van, but did not have TPMS sensors fitted (the general concensus in this forum were that they were a pain in $#@%) and I was prepared to live for the winter months with the TPMS warning light permenantly lit.....

....Except, after fitting the new wheels (and leaving the originals in my basement), the TPMS warning light did not come on.

Concerned that I might have a fault, I put the original OEM wheels back onto the vehicle and took it to my local Dodge dealer. They 'tested' the system and reported that the vehicle TPMS system was working fine.

So I when home and changed the wheels again - still no light.

I could not get back to the dealer for a couple of weeks, so drove around with the winter wheels on the vehicle. After 6 days, the TPMS warning light came ON and remained on.

I took the van back to the dealer and explained that the light - although now showing on the dash - had taken 6 days to appear. they explained that this was normal as I had not driven the van for a long enough distance for the system 'realise that the sensors were not there'...

Ok - I can accept that - just...

so, I drive the van for a few more days with the light on, then one day as I am driving across town, the light goes 'OFF'!!! and stays off for the next few days....

So I go back to the dealer - This time, another mechanic - the "TPMS EXPERT!!" apparently - said that the van is fine and the system had finally re-learnt that it was working in 'winter mode' re: none of the wheels had sensors, therefore the system had deactived itself. Apparently, it would come on again automatically when I put the original OEM wheels back on in summer...

So once again, I took the vehicle back and drove it around.

Now, once again, as I was driving, the light has come back 'ON' and has stayed on for the last few days.

So my question to you all is this: "What the $#% is going on? Is my system working or is it not?"

Thanks for reading as I vent.....

Welcome to DF
Here is what I have found so far, But I am still looking for the answer to your question.

22 - Tires and Wheels/Tire Pressure Monitoring/Operation
OPERATION


BASE TIRE PRESSURE MONITORING
The tire pressure monitoring system (TPMS) is designed to operate without loss of function for all OEM tire construction for this vehicle. Sensors, mounted to each road wheel as part of the valve stem, transmit an RF signal indicating their individual pressure to a receiver located in the Wireless Ignition Node (WIN). These transmissions occur approximately once every minute at speeds over 15 mph (24 km/h). For more information on sensors, (Refer to 22 - Tires and Wheels/Tire Pressure Monitoring/SENSOR, Tire Pressure Monitoring (TPM) - Operation).

If the TPM system detects that the tire pressure in any road tire is going low, beyond the Low Pressure (lamp) ON threshold (see placard table below), the TPM system will continuously illuminate an indicator lamp. If a system fault is detected, the indicator lamp will flash on/off for 75 seconds, then remain on solid.

If the WIN detects a warning or fault condition at ignition key "ON" it will wait ten seconds +/- 10 % before sending the first request to illuminate the indicator lamp. This will assure that the display module has concluded its bulb check period. The display module will request a chime once per ignition cycle for each "warning" or "fault" condition detected. A "warning" or "fault" condition will remain enabled until the problem causing the condition is corrected and removed/reset.

The WIN shall continuously monitor for the receipt of tire pressure RF message transmissions from the wheel sensors during both the ignition key "ON" and key "OFF" cycles. The wheel sensor ID’s and the location of each sensor (e.g. Tire 1, Tire 2 etc.) are learned by the WIN from the Front Control Module (FCM) configuration during the initial Manufacturing Plant Process, or during a service procedure, as required.

The TPM System will continue to warn the driver of low tire pressure as long as the condition exists, and will not turn off the indicator lamp until the tire pressure is at or above the Low Pressure (lamp) OFF threshold (see placard table below). The system will automatically update and the TPM indicator lamp will extinguish once the updated tire pressures have been received.

Tire pressure will vary with temperature by about 1 psi (6.9 kPa) for every 12°F (6.5°C). This means that when the outside temperature decreases, the tire pressure will decrease. Tire pressure should always be set based on cold inflation tire pressure (placard pressure). This is defined as the tire pressure after a vehicle has not been driven for more than 3 hours (and in outside ambient temperature). The tire pressure will also increase as the vehicle is driven; this is normal and there should be no adjustment for this increased pressure. For a system fault, the system will return to normal once the WIN receives a valid transmission from that sensor location.



PREMIUM TIRE PRESSURE MONITORING
The tire pressure monitoring (TPM) system is designed to operate without loss of function for all OEM tire construction for this vehicle. Sensors, mounted to each road wheel as part of the valve stem, transmit an RF signal indicating their individual pressure to a receiver located in the TPM module. These transmissions occur approximately once every minute at speeds over 15 mph (24 km/h). For more information on sensors, (Refer to 22 - Tires and Wheels/Tire Pressure Monitoring/SENSOR, Tire Pressure Monitoring (TPM) - Operation).

If the TPM module detects that the tire pressure in any road tire is going low, beyond the Low Pressure (lamp) ON threshold (see placard table below), a chime will sound and the indicator lamp will turn on. In addition to the chime and lamp, a graphic display of the pressure value(s) and position of the low tire(s) will flash in the Electronic Vehicle Information Center (EVIC). Once pressure in the suspect tire(s) raises above the Low Pressure (lamp) OFF Threshold (see placard table below), and the TPM module receives a valid transmission from the sensor, the lamp will go out. If a system fault is detected due to a missing sensor signal, in addition to a chime and a indicator lamp flashing, a “Check TPM System” text message will be displayed in the instrument cluster, and the tire pressure graphic display will have "- -“ in place of the pressure value. After the flash sequence, the TPM indicator lamp will remain illuminated. The system will return to normal once the TPM module receives a valid transmission from that sensor location. If a system fault is detected, the indicator lamp will flash on/off for 75 seconds and then remain on solid.

If the TPM module detects a warning or fault condition at ignition key "ON" it will wait approximately ten seconds before sending the first request to illuminate the indicator lamp. This will assure that the display module has concluded its bulb check period. The display module will request a chime once per ignition cycle when a "warning" or "fault" condition is detected. A "warning" or "fault" condition will remain enabled until the problem causing the condition is corrected and reset.

The TPM module shall continuously monitor for the receipt of tire pressure RF message transmissions from the wheel sensors during the ignition key "ON" cycle. The wheel sensor ID’s and the location of each sensor (e.g. Tire 1, Tire 2 etc.) are learned by the TPM control module using signal strength and direction of wheel rotation as received by the TPM module from each of the sensors, and updates the graphic display when necessary or during a service procedure, as required.

The TPM System will continue to warn the driver of low tire pressure as long as the condition exists, and will not turn off the indicator lamp until the tire pressure is at or above the Low Pressure (lamp) OFF threshold (see placard table below). The system will automatically update and the TPM indicator lamp will turn off once the updated tire pressures have been received.

Tire pressure will vary with temperature by about 1 psi (6.9 kPa) for every 12°F (6.5°C). This means that when the outside temperature decreases, the tire pressure will decrease. Tire pressure should always be set based on cold inflation tire pressure (placard pressure). This is defined as the tire pressure after a vehicle has not been driven for more than 3 hours (and in outside ambient temperature). The tire pressure will also increase as the vehicle is driven? this is normal and there should be no adjustment for this increased pressure. For a system fault, the system will return to normal once the TPM module receives a valid transmission from that sensor location.

For both the Premium and Base TPM, the recommended "Placard Pressure", "Low-pressure Threshold" (Low Pressure ON) and “Hysteresis Pressure” values for the tires installed on the vehicle, are learned by the WIN or the TPM module from the Front Control Module (FCM) configuration during the initial Manufacturing Plant Process, or during a service procedure, as required. The WIN upon learning the placard pressure via the bus (through a matrix within the WIN software) applies the appropriate "Low Pressure Threshold" and "Hysteresis Pressure” values.

To determine the pressure thresholds for a vehicle, refer to the Tire Inflation Pressure (Placard) Label, and then apply the placard pressure to the following table. The Low Pressure OFF Threshold is defined as the Low Pressure ON Threshold plus the Hysteresis Pressure value.

For further information, refer to the Owners Manual or the Appropriate Diagnostic Information.



TPM THRESHOLD PRESSURES


NOTE: To determine the pressure thresholds for a vehicle, refer to the Tire Inflation Pressure (Placard) Label found on the Driver's B-Pillar, then apply the placard pressure to the following table.

Cant find any official Info on your concern, But base on my experience, when u remove all 4 TPMS, TPMS light goes ON and Off randomly, I've seen cars with Aftermarket wheel on, no sensor, yet no light once in a while.

When it is ON/Blink, it means it can't find any sensor. When it is OFF, it is in the process of "Looking for sensors". Hence, Whenever I replace a WIN module, or Reset a WIN module, or disconnect the battery, All TPMS value in the computer will show up Blank, but light will not be ON.

The Winter Mode is BS, it is probably in Programing/searching mode. I dont think there is anything wrong with your car.

If you want to verify is your TPMS sensor is working properly, Simply install your original wheel, drive it until it relearn, then Deflate one tire to like 25psi, see if the warning light pops up.

Steak59 - Thanks for the response. Your last suggestion - changing the pressure on the OEMs - is one that I will try -> just not today as it has just snowed here!:p.

What is very interesting in your response is your statement:
"...When it is ON/Blink, it means it can't find any sensor. When it is OFF, it is in the process of "Looking for sensors". .."

This would explain explain the scenario which I am seeing, if I could only understand the circumstances in which the system would switch from 'Can't Find sensor' to 'looking for sensor'...

Any Ideas?

Master Tech - WoW! fantasic detail there. It has taken me a few minutes to absorb the data you provided.

What I can say is this:
1) I must have the 'Basic' system, as I do not have the EVIC fitted to this vehicle;
2) Some key points which I pulled from the data your provided:

• "..These transmissions occur approximately once every minute at speeds over 15 mph (24 km/h).." - As you may have gathered from my initial post, most of my driving is in town, therefore achieving speeds greater than 15mph for more than 60 secs may not always happen. So what does the system do when the vehicle is travelling at less than 15mph?
• "..If a system fault is detected, the indicator lamp will flash on/off for 75 seconds, then remain on solid..." - This is exactly what happens with my vehicle. I did not realize that the 75secs flashing before going solid meant something. Now I know that is means 'system error' - question is, is the error due to a fault with the system or because the system cannot find four wheel sensors?
• You information states that the light will stay on until the fault is rectified - what circumstances would cause the light to go 'off' when the wheels still do not have sensors? Is Steak59 onto something when he siad that it would go off when it entered "discovery mode"?

Thank you so much for putting time into helping me....

The WIN module is Constantly searching for sensors, or New sensors.
I guess if you park the car long enough, the WIN will erase the fault code.
Or do you have a garage where you park your car next to all your old tires?

You don't necessarily have to install all 4 OEM wheels, you can Pile them all up inside your car, the WIN module will pick up the sensor.

TPMS - Frot & Rear Whell
 

What if I mount the front wheel in the rear and vice versa.
the system can know which wheels to be measured or show the wrong value (wheels) on the display?

It will learn the position of the wheels after a rotation.

does the spare have a sensor?

no it does not