Temp Guage probs? Dash insert stuffed?

[AndymacA4]

Hi all, few issues on my 2001 A4 1.8T SE

The temp gauge works intermittently. Sometime shows temp, sometimes sits on the 50 degree mark, no movement.

Audi say it needs a new dash insert at a cool £350 or so.

Is this a fixable issue? As when it works it is reading fine?

The temp sensor has been replaced and is collecting correct data.

Ta

Andy

 

[ScottyP45]

ive seen others with the exact same problem mate, it does indeed seem to be a dash fault, there are companies that repair dash modules on the net, or you could try a second hand replacement but bear in mind that the immob is tied into the dash module and it will need recoded if you fit a replacement. Maybe buy a warranty from Tesco then try and get ot repaired under that....?

 

[Marko]

Is it not a case of a new gauge! Mine has been goosed for over 12 months. It sits at 130 when ignition off. If I do a drive to get the engine hot it may return to 90 after a time. It flickers as though it's shorting somewhere. Very annoying as I've no idea of engine temps.

 

[AndyMac]

You can get the temps to show on the climate control. Just press recirc & up arrow, then scroll up to 49c using the + button, then press recirc again to get the reading. Press recirc & up arrow again to go back to normal.
http://www.wak-tt.com/climate/climatecodes.htm

 

[Marko]

I didn't think these worked for the B6 model? I thought it was only the TT and B5?

 

[ScottyP45]

Marko I think its a fault in the circuitry in the instrument cluster that drives the gauge, rather than the gauge itself. Others have swapped the temp gauge and senders to no avail, probably a faulty logic chip driving the device.

Senders pull in analogue data, like a varying voltage, then that has to be converted to a digital signal for the ecu by an A/D converter, then the output driving the gauge is back to analogue voltage again, a lot can go wrong in between.

 

[Marko]

Marko I think its a fault in the circuitry in the instrument cluster that drives the gauge, rather than the gauge itself. Others have swapped the temp gauge and senders to no avail, probably a faulty logic chip driving the device.

Senders pull in analogue data, like a varying voltage, then that has to be converted to a digital signal for the ecu by an A/D converter, then the output driving the gauge is back to analogue voltage again, a lot can go wrong in between.

Thanks for the info. It's even worse than I thought. I'm not paying out £££ of pounds to get a new cluster. The gauge at the moment is sat at it's max beyond 130! I'd like to know of any varying temp problems. Does anyone know if:-

1. this DIS shows a warning for high engine temp as well as fluid level?

2. Could the temp warning be set to a lower temperature to warn early of higher that 90c temps.

Cheers.

 

[Marko]

Marko I think its a fault in the circuitry in the instrument cluster that drives the gauge, rather than the gauge itself. Others have swapped the temp gauge and senders to no avail, probably a faulty logic chip driving the device.

Senders pull in analogue data, like a varying voltage, then that has to be converted to a digital signal for the ecu by an A/D converter, then the output driving the gauge is back to analogue voltage again, a lot can go wrong in between.

Thanks for the info. It's even worse than I thought. I'm not paying out £££ of pounds to get a new cluster. The gauge at the moment is sat at it's max beyond 130! I'd like to know of any varying temp problems. Does anyone know if:-

1. this DIS shows a warning for high engine temp as well as fluid level?

2. Could the temp warning be set to a lower temperature (vagcom) to warn early of higher that 90c temps.

Cheers.

 

[ScottyP45]

I don't know exactly whether the dis warns of high temperatures but they are visible in vagcom, so i would expect that it would show a warning when overheating starts.

As for the warning limit i think that would be set by the software in the ecu, in effect a limit pre-set by the engineering values for the engine would be likely so that no damage occurs and is probably unchangeable, tho it should be set to a safe level so your probably ok there anyway. Theres a company called "BBS Reman", they repair dash inserts and ecu's, check out their website or give them a ring and ask their advice.

They have seen this before and know what causes it in detail (£150 for a dash rebuild):
http://www.bba-reman.com/catalogue/DetailedProduct.aspx?DetailedProduct=278

 

[Marko]

Thanks for the link and your thoughts. Appreciated.

 

[AndymacA4]

Now fixed,

I took the car to an Audi dealer. They plugged the car into a diagnostic machine and manually tested the dials. They should all have moved to the far right, then the far left then stopped in the middle of the gauges. All did except the temp gauge which only flickered then just stopped. The car was in for about 45minutes, the part needed was a new dashboard instrument insert and was £250 and fitting was another £70. The new dash insert panel works now. I have also got the warning beeper back which would appear to have been connected to the problem. New panel, now beeps when the lights are left on when the door is opened.

Both keys were needed as Audi re-coded the keys to the car as part of the procedure.

The method for getting the climate control to show other data does not work for my car, so I assume it is indeed just for TT and B5 cars.

 

[Marko]

I've done that test on my car and my temp gauge just flickers about! Is the dashboard instrument insert the whole lot including gauges? £320 for a faulty temp gauge.. not sure I fancy paying that!!

 

[AndymacA4]

Yep that replaces the whole panel inc. the speedo, info panel, fuel gauge and rev counter. All in one. Driving with a knackered gauge doesn't affect the car, or the ECU. The gauge is at the end of the line. All temp monitoring for car health comes before this.

Your call. Due to personal taste I guess.

 

[Marko]

Yep that replaces the whole panel inc. the speedo, info panel, fuel gauge and rev counter. All in one. Driving with a knackered gauge doesn't affect the car, or the ECU. The gauge is at the end of the line. All temp monitoring for car health comes before this.

Your call. Due to personal taste I guess.

Yep indeed, cheers.

 

[ScottyP45]

or get it repaired at BBS for £150 if you can do without the car for a couple of days.

 

[Marko]

currently got my dash insert and temp gauge out. There were several dry joints on the back. I've also taken the back off where the magnetic coils and cogs are. Assembled but not checked yet and too dark to carry on. Will update if I managed to fix. Could save folks a packet if it's only the dry joints.

 

[s-line stu]

Andy,

I had a similar problem when I took my car for service at Stafford Audi.

They didn't tell me what the cause was but fixed it during the service which took 1 hour in total (service car valet and temp gauge fix).

They said it was £93 but as it was the first time i'd been to them for service they'd not charge me and claim it from Audi as a warranty item.

So whatever it is it can't be too difficult if they did it so fast. I ended up paying £79 for the service which was cheap anyway so with this fix for free and a valet thrown in it was an absolute bargin.

Where are you based - it may be worth going to them if they're not too many miles away?

Not suggesting you'd be as lucky as me but I'm sure they're much cheaper then most Audi dealers and would know what it is straight away.

Stu

 

[AndyMac]

Typical Audi I'm afraid (not Stafford), they just replace parts until the problem goes away. Sounds like Stafford actually know what they're doing and will take the time to cure the problem properly as well as saving their customers a small fortune. Well done Stafford Audi, there's not many dealers left who will go that extra mile and actually care.

 

[Marko]

I suspect S-lines Stu's could have been the temp sender. That's as far, I believe Audi will go at fixing the temp gauge. The sender makes them behave very erratic. I replaced my sender sometime ago to no avail. £20 and 20 mins of my time.

Anyway, gauge all back together and not a peep! It doesn't want to move. All the dials at the back use the same setup, it's like a stepper motor affect, two coils and rotating magnetic gear. Trouble is they are built not to be rebuilt. I need a new temp gauge and all will be fixed. The cluster itself is fine. The fuel and temp gauge are easily removed, the others aren't. Back to scouring then net..........

 

[Marko]

OK it's fixed. I ended up finding another dash insert from a breaker. A very good breakers in Lancashire. £40 for the whole unit inc DIS. The unit was a little scratched so for now I just took the temp gauge out and placed into by dash insert. Jobs a good one.

The gauge is not analogue, it is digital driven by the stepper motor in a white box. While it looks smooth it can only display discrete steps. If it is a pulse sender then there is not a lot of converting to be done to get a digital signal. I suspect that the fault I had was most likely to have been the dry joint I identified. Should have tested before I took the white plastic off!!! There is not really much to go wrong in the digital part of the circuit, it takes in the pulses from the sender, works out how much the temperature has gone up or down since the last sample and sends out a few pulses to the gauge to move it to the new position.

Anyone with a wonky gauge, check for dry joints first, could save you a packet.