beran earms

So I now have the new T/B in with a replacement audi tensioner, ? is the tension light comes on after the engine is warmed up a bit, Maybe I read wrong, but isn't the light obsolete with a PKT? I had this set up in before, just a refresh, but I never noticed a warning light, so ???
thanks JD

Kevin in Atlanta

You did ground the TB connector to the block, right?

beran earms

Hey guys, I just want to bring up this issue again. I have checked the connection, all seems good. It appears that when I start the engine, I have no light, after maybe 5-10 min. the central warning light comes on indicating belt tension. If I continue to drive and get engine temp. up to normal operating temp. and shut down, then restart, then continue to drive, I believe the light does not come back on. Does this sound even possible, I'm a bit worried to keep trying to research and find out exactly when and why this occurs, not sure if I'm tempting fate. I guess the question is, does ,or can the warning light still apply when using a PKT ?

Bertrand Daoust

The belt tension warning system is not used (unfortunately) with the PKT.

Of course, it is still there but not "connected" with the PKD.

Like Kevin mentioned, probably it's not grounded properly.

It's normal it gives you a warning after few minutes when you start the car.

Why it doesn't come back (if so) when the engine's warm? Can't say. Expansion?

Check the ground connection first.

If everything was good when you install the tensioner (read piston extension was good-
belt tension was good) then everything should be ok.

Good luck.

beran earms

Thank you, You have to admit it still is a little worrisome to just get in and go! By the way, I really wanted to meet you and check out you beautiful Cobalt Blue when you were here for Parade. Unfortunately mine was torn apart.

Bertrand Daoust

I would say annoying more than worrisome!

Do you plan to go to Frenzy this year?
I'll be there.

beran earms

Bringing this up again, I know it has been discussed before, but can someone please explain the "3 minute" feature with the CWL? Once again, I have a PKT, and understand the light is not needed now, but how and why does it come on ? Is it ONLY because of a bad ground? I'm asking this because, I'm very embarrassed to admit, I hired a "928" guy to do the work, and I was not able to get in there first hand, I had no time tho' I wish I had. I don't want to be redundant, but any info would be great.
Thank you JD

FredR

The alarm has no role in the original PKT system- to stop the alarm the lead has to be grounded or otherwise defeated.

Christopher Zach

I'm actually chasing down what might be a false warning light myself (checked tension with the tool, it's fine, comes on at high RPMs). For your case there is no belt checker, so it can't be that :-)

If you have grounded the belt tension wire at the engine to ground and it's still coming on your problems might be:

A loose connection at the CWS: It's possible that the connecting wire has a break or loose connection somewhere between the end and the CWS. I *think* that the wire is held to +12v with a 10k resistor in the CWS, then is of course grounded. If the wire comes loose for even an instant the signal triggers an SCR which lights the light.

Another thought I have been looking at is that something can raise the voltage on the line high enough to trigger the light. Noise maybe; I found that 2 of my spark plug wires were right on top of the sense line. That might do it.

Or the CWS is wonky. Could happen.

Take it one step at a time, it's something.

Wisconsin Joe

Well, the "three minute feature" is an interesting thing. It tells me that the engineers knew that the belt tension wouldn't be ideal when the engine was "ice cold."
The engine has to warm up a bit (and expand) for the tension to be enough that the tension arm will stay in constant contact with the tensioner.
Apparently (just did a quick search) the expansion rate for aluminum is twice that of steel.

I have the identical situation. I put a PKT in two years ago, and started seeing the "Belt Ten" light this summer. Sometimes it comes on right away (after 3 min), sometimes it waits a while, sometimes it doesn't come on at all.
Since the belt tension light is a function of loss of continuity to ground, I'm guessing that I have either a broken wire or a bad connector somewhere that "wiggles" enough to break contact, loses continuity with ground and triggers the light.

So far, I've checked the connector on the belt cover, and bounced the wiring harness around a bit, but I haven't really dug into the issue.

beran earms

I want to mention that the last time I drove it, the light came on and I reset it by shutting off while driving, then timed very close to 3 min., I did this several times and paid close attention to driving circumstances, such as acceleration, speed, turning , bumps, temp. everything I could possibly do to get it to trigger. Seems like it has everything to do with the 3min.

Wisconsin Joe

Can you get the connector on the front of the TB cover loose? It's a bit of a 'toughie' to get off.

If so, check it for continuity to ground. That's where I plan on starting...

When I actually get to it.

PorKen

3 minutes is built into the warning system so you are likely missing ground from the get-go.

PorKen

FWIW, I'm working on a kit to implement the idea for a PKT warning light set out in the thread below.
I think this sensing method is at least as good, if not better than the factory 'sensor'.
https://rennlist.com/forums/928-foru...ing-light.html

Kudos to Alan for testing it out! (link jumps to page 9)
https://rennlist.com/forums/928-foru...l#post14255673


Mostly, I'm looking at ways to connect to the female spade terminal outside of the timing belt cover so there's no danger of anything getting caught in the belt.

beran earms

Ken, I will be looking out for this! I'm kinda PO'd at myself for not doing my own work, my car is in worse shape now than when it went in for work, I will need to find the time, roll up the sleeves and get it done! Thanks everyone!!