TMPS Retrofit

[ScottD3]

Good Afternoon all,

In a bit of a random impulse buy I bought a TMPS module for my car cheap and then thought, I better find a way to retrofit this to my car.

Has anyone retrofitted TMPS before?

I remember Del bought all new sensors for his wheels at about £400.

I've seen other sensors for about £40 each with the same frequency and assume they will fit but they have different part number.

Can anyone confirm what sensors are required and if others are compatible?

[mattylondon]

Hi Scott.

The TPMS module (J502) is located under the rear bench seat and is powered with a 5A fused Terminal 30 supply. That part of the wiring is fairly simple. Then take the CAN wires to the CAN separating connector block on the left hand side. Simple, but you've got to remove all of the internal trim.

Next part is to wire each tyre pressure sensor aerial back to the J502 module. Each aerial is located behind each wheel housing liners, a bit of a pain but do able.

Did you get the aerials and retainers with the module you bought?

Can't comment on what other sensors will work.

Hope that helps

[ScottD3]

I only got the module.

I did ask them for the sensors and mounts but they did not have them.

TPMS parts seem so much cheaper from Poland.
Apart from the sensors, they are still costly.

Full interior strip is not really a bad thing.
I can give it a deep clean as well then.

Thanks for the image, I did wonder where the module went.

[M-A8]

Basically the sensor in question here is 7PP907275F

Which is not the D3 (4E0) part number but it's an Audi sensor which is compatible with all Audis fitted with TPMS, even 2004-2010 A6, but not the A8, only 2010 A8 up.
It works on the same frequency what D3 part number 433MHz.

So the type of the aerial on A6 is same as on the A8 therefore the signal or its "coding" (sorry my technical knowledge here is poor) or the way it's send is exactly the same !?

Obviously the ECU which contains software needs to be D3 specific which is fine, but the aerials and sensors if they are Audi oem ones not, or do they ??
In my head aerial is an aerial and pressure sensor is a pressure sensor.

Thank you in advance who could share some technical knowledge on that

[M-A8]

...also, over the years I have noticed that Audi parts which have the same middle 6 numbers are almost or same parts, if there is a difference then its always a cosmetic one.
For example:
The A5/S5 steering wheel or airbag is exactly same as D3 (function, connection, fitting), yes, the first 3 numbers/letters are different but they are only a platform IDs (4E0 Audi A8, 4F0 Audi A6 and so on).

For example S5 steering wheel PN is 8P0 419 091 DT and A8s is 4E0 419 091 AC and A6s is 4F0 419 091 AQ
Fact is all three are exactly same wheels and they will fit each of the models.
Usually, this is what I have noticed so I'm not saying it's 100% true, the last letter or two will describe the cosmetic difference or extras such as paddle shifters or being just a later revision of the same part, but they are same wheels using same air bags and same buttons.

Same think I found out when fitting chrome window switches, the part number is A3 part number and they are from A3 not A8, they were never available in A8, but they are the same part with a cosmetic difference and guess what, all 6 numbers in the middle of each part number are same.

Where I'm heading with it is that the TPMS wheel sensor which I can get brand new for £30 OEM Audi part starts with 7PP not 4E0 or 4F0 but the 6 middle digits are the same.
On top of it they both are 433MHz frequency as clearly printed on them and there is no physical connector so it's not like they are same but they take different plug.

Sensor in question is 7PP 907 275 F
A8/A6 sensor is 4F0 907 275 D

[mattylondon]

They may well work if they have the same PR Code of 7K3, that's the 433MHz version. The only head scratching I have is you go about registering the new sensor ID's to the TPMS module and its location on the car, front left etc... Can this be done with VCDS? And I assume the sensor ID will be physically marked on it?

[ScottD3]

So there is a chance of them working?

Only one way to find out.

Unless anyone got any other input?

Matty, I'm not sure how you register new sensors to TMPS. Not thought about that.

[mattylondon]

I found this

Audi 2004-2006 A6/A8 all

Audi utilizes a sophisticated computer system to monitor tire pressure. If a low tire pressure warning light is observed, simply filling the tire(s) to specified pressures should shut the light off. If this does not shut off the light, then follow the "changing a wheel" initialization procedure.
Changing a wheel

When you change a wheel, the new tire must be initialized.

Press the "CAR" function button.

Select Systems in the CAR menu.

Select Tire pressure monitoring.

Select Initialize wheels.

When you change a tire, you must perform the Initialize wheels procedure. You must do this each time to change a tire. The procedure can take up to 20 minutes. During this time, the tire pressure and temperature will not be displayed because the sensors are being "broken in" and the learning process is taking place.

During the learning process the tire pressure monitoring system is only partially available It only warns when tire pressure drops below the minimum permissible specified pressure. This can indicate one or more tires as well as the spare tire. If this is the case, the warning symbol appears together with the message Tire pressure!

If this still does not fix the problem, contact your authorized Audi dealer for assistance.

And a useful PDF here

http://uberlame.com/a6_tsb/TPMS/TPMS%20Overview.pdf

[M-A8]

Interesting PDF document, reading it now.

Re registering locations of the sensors I think it's all very simple.
Each wheel has sensor which has own aerial
Each aerial is wired to the ECUs allocated pins in the connector therefore Car knows which sensor is on which wheel ?!?!?

[mattylondon]

So do the sensor and aerial only work in close proximity? Then what about the spare as it's between two aerials? Time to dig out my Bosch Automotive Electrics and Electronics, I need answers.