Chrono Pack Oil Temp Sender Location?

NC TRACKRAT · #1 06-09-2009, 03:05 PM

Have searched the threads. There is supposition that there isn't one...That it's input is somehow miraculously calculated by some Leprechaun in the engine and sent to the chrono pack gauge. Anyone out there know the facts? It's certainly not a drain plug sending unit. Is it in tandem with the oil pressure unit on the oil filter housing? It's not shown on any parts diagrams. Any MINI techs learn this bit of "minutia" (pun intended)

MINIdave · #2 06-09-2009, 03:13 PM

You sure it's not in the drain plug?

My oil temp sensor replaced the oil pan drain plug.

Find your drain plug and see if there's a wire attached. If so, that's it!

BlimeyCabrio · #3 06-09-2009, 03:19 PM

Do we know that the "Oil Pressure Switch" in the filter housing is NOT sending a pressure signal that the ECU is interpreting to either light an idiot light or run the gauge? That's my suspicion. The Diagnosis Without Guesswork book is silent on this topic surprisingly... it's usually very complete. The Gauges are definitely controlled by the computer... they are not "traditional" gauges with hardwired sensors/senders.

Edit: DEFINITELY NOT in the drain plug.

NC TRACKRAT · #4 06-09-2009, 06:09 PM

I can assure you that it's not the drain plug. There is a traditional oil pressure sender at the filter hsg. but it supplying also a temp reading, possible but doubtful. Only one p/n is listed. Idiot light senders are usually set to fire warning light at a very low value and not variable output. Gauge is analog, not digital, indicating variable voltage. I suspect there's a sender for this gauge somewhere.

BlimeyCabrio · #5 06-09-2009, 06:25 PM

I'm still betting it's the sender on the oil filter housing. Put a voltmeter on it... I bet it's not just a "switch" for the idiot light.

As for temp... no idea where that's being read.

Only reference to oil pressure in RealOEM:
http://www.realoem.com/bmw/partsearch.do?keywords="oil+pressure"&model=RH33&m ospid=48019

NC TRACKRAT · #6 06-09-2009, 07:48 PM

I'm looking for the TEMP sender, not the Pressure sender...I know the Pressure sender is on the Oil Filter hsg. and it does send to the Chrono Pack Oil Pressure gauge, not an idiot light.

Partsman · #7 06-09-2009, 07:57 PM

If you would like to forward me the last 7 digits of your VIN, I will research it tomorrow at work.
My lead tech and I touched on the subject a while back, but we didn't have a Chrono Pack specific VIN to go by.

BlimeyCabrio · #8 06-09-2009, 08:04 PM

Duh.. wish I could read.

Sent a PM to a couple of gurus... stay tuned.

BlimeyCabrio · #9 06-10-2009, 08:02 PM

So I asked frenchie, who knows more about MINI control systems and sensors than just about anyone else I know... and he's stumped also. Can't find it on any wiring diagrams or parts lists. Wasn't covered in any training he had. Guessed (like me) that maybe it's integrated into the pressure sender - but it's only a guess.

**SRTech** · #10 06-10-2009, 10:31 PM

Quote:

Originally Posted by BlimeyCabrio

So I asked frenchie, who knows more about MINI control systems and sensors than just about anyone else I know... and he's stumped also. Can't find it on any wiring diagrams or parts lists. Wasn't covered in any training he had. Guessed (like me) that maybe it's integrated into the pressure sender - but it's only a guess.

I and a mechanic I know who works for a MINI dealership have the Chrono Packs on our MINIs. Several years ago we both tore our cars apart looking for the sender. It doesn't exist. The signal must be computer generated by the signals from other sensors so there is no direct temperature measurement. The gauge doesn't give me a feeling of confidence.

Steve

BlimeyCabrio · #11 06-11-2009, 05:13 AM

It would be pretty interesting to rig an outboard oil temp gauge on a Chrono Pack car and compare readings... just to see how accurate the chrono is or isn't. I'm too lazy...

NC TRACKRAT · #12 06-11-2009, 07:21 AM

DANG!

Someone, somewhere in the bowels of BMW/MINI Engineering must know the secret of how and where this input is generated and the relative accuracy of it. If it is computer-generated, from what sensor/s is the data being taken?

MiniMacPR · #13 06-11-2009, 07:49 AM

I am very interested in this also. It's the chrono pack gauge I usually watch the most. According to it, my oil temp gets silly hot at the track. I agree that it has to come from some sort of variable input cause that gauge moves around a lot and in direct relation to car use/abuse

**SRTech** · #14 06-11-2009, 08:13 AM

Quote:

Originally Posted by MiniMacPR

I am very interested in this also. It's the chrono pack gauge I usually watch the most. According to it, my oil temp gets silly hot at the track. I agree that it has to come from some sort of variable input cause that gauge moves around a lot and in direct relation to car use/abuse

I definitely think the water temp has a lot of influence. Unfortunately, it's hard to guess at the real temps because the gauge scales aren't linear and there are few numbers.

I do plan on adding a oil temp gauge to my Racepak system.

Steve

NC TRACKRAT · #15 06-11-2009, 01:52 PM

Both the water temp and the oil temp gauges on the chrono pack ARE linear. Water temp stays at 195F on track or off but, on track, oil temp raises to just below the third mark which is 265F....(even with a big oil cooler!) As soon as I get off track and take a cool-off cruise thru the paddock, it immediately drops. Base mark is 100F High mark is 320F, Mid-mark is 210F. I suspect that, wherever the temp is being sensed, it's somewhere in the oil galleys, very near the combustion chambers.

**SRTech** · #16 06-11-2009, 03:37 PM

Quote:

Originally Posted by NC TRACKRAT

Both the water temp and the oil temp gauges on the chrono pack ARE linear. Water temp stays at 195F on track or off but, on track, oil temp raises to just below the third mark which is 265F....(even with a big oil cooler!) As soon as I get off track and take a cool-off cruise thru the paddock, it immediately drops. Base mark is 100F High mark is 320F, Mid-mark is 210F. I suspect that, wherever the temp is being sensed, it's somewhere in the oil galleys, very near the combustion chambers.

Yes, the scale is linear, but we'll see if the movement is accurate when I put a gauge with a sending unit on it. Remember, the part number for the water temp sending unit is the same for the Chrono and the standard gauge, and we all know how accurate the standard gauge is.

Steve

NC TRACKRAT · #17 06-11-2009, 05:26 PM

Steve-
Keep me posted. Are you going to use a drain plug sending unit? It'll probably give you the best, real-world temp. I can't think of another location that's available w/o some serious modification.

**SRTech** · #18 06-11-2009, 06:02 PM

Quote:

Originally Posted by NC TRACKRAT

Steve-
Keep me posted. Are you going to use a drain plug sending unit? It'll probably give you the best, real-world temp. I can't think of another location that's available w/o some serious modification.

I hate that location. I have a spare oil pan I'm going to drill and tap where the sending unit won't be exposed to damage or have to be removed every time I change my oil. Now, if I can only find the time to work on my car.

Steve

NC TRACKRAT · #19 06-11-2009, 06:15 PM

I really don't think that's such a bad location. If it gets damaged there, you've got worse problems than the sending unit! Just one wire to disconnect b4 changing oil.

Partsman · #20 06-11-2009, 06:51 PM

My lead MINI tech is looking into this for me, but the shop has been slammed the past few days. He is going to get me the wiring diagram for the Chrono Pack cluster.

**SRTech** · #21 06-11-2009, 07:30 PM

Quote:

Originally Posted by Partsman

My lead MINI tech is looking into this for me, but the shop has been slammed the past few days. He is going to get me the wiring diagram for the Chrono Pack cluster.

That should be interesting. I hope it comes with a description of operation if the wires all just end up in one of the computers.

Steve

**SRTech** · #22 06-11-2009, 07:36 PM

Quote:

Originally Posted by NC TRACKRAT

I really don't think that's such a bad location. If it gets damaged there, you've got worse problems than the sending unit! Just one wire to disconnect b4 changing oil.

I've just seen too many of the OEM sending units over-torqued which tends to destroy the threads. There are only 4-5 threads on the sending unit. Fortunately, the OEM drain plug has more theads so you can still plug the hole while the owner decides if the gauge is worth the cost of the thread repair.

Steve

chris.j.lamb · #23 07-27-2009, 04:01 AM

The chronopack calculates the oil temperature from the water temperature and revs and throttle postion,. There is no direct oil temp sender.......
DO NOT trust it.

pmello · #24 07-27-2009, 04:27 AM

I had a 2005 with a crono pack. We hitched up an AIM gauge cluster via CAN bus. The oil temp is on the CAN bus. The sensor seemed very accurate. I remember readings of 13deg's on startup in the winter.

NC TRACKRAT · #25 08-20-2009, 09:43 AM

At start-up, low temp, I'm sure it's quite accurate but at elevated temps the calculations it makes just don't make real-world sense. I'm wondering if the filler plug sensor 8940004581 used with the console temp gauge could be connected to the ChronoPac gauge with better accuracy. Input NE1?