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DISCUSSION => Engine + Driveline => Topic started by: rhogg on February 15, 2009, 10:42:12 AM

Title: Which sensor send the temp to my Dash?
Post by: rhogg on February 15, 2009, 10:42:12 AM

After changing my starter, and refreshing the "mess under the intake"  everything is running fine except my dashboard temperature gauge which is getting power but not showing any tmeperature.

So REAL OEM shows:

http://www.realoem.com/bmw/showparts.do?model=AJ93&mospid=47318&btnr=11_1505&hg=11&fg=15

Is part #6 the sensor that connects to the dash gauge?

There is no difference between this connector and the one that plugs in below the Oil filter. Is there any way to differentiate them?

I figure I have either plugged them into the wrong spot or my temp sensor is loose.   I wanted to check before I take off the intake (again!)

Thanks.

Title: Which sensor send the temp to my Dash?
Post by: ghoulama on February 15, 2009, 11:01:03 AM

yes, part 6 is the sensor for the gauge. it should have 1 wire. part 8 is the temp sensor for the computer - it has 2 wires. when i did my under the intake cleanup i pulled the wire for the gauge loose and had to reattach it.

Title: Which sensor send the temp to my Dash?
Post by: JHZR2 on February 13, 2010, 12:01:41 AM

Can anyone comment on thedifficulty to access/disconnect the sensor harnesses, and also to replace the sensors?

My temp gauge is flaky, but it is not the nut inthe gauge, I've cleaned the connections and tightened it.  I need to check the sensor and/or replace it.  

Since there is tons of snow here, it is toughto go out and fiddle much. If anyone who has worked with these before could comment, I'd appreciate it.

Thanks!!

Title: Which sensor send the temp to my Dash?
Post by: Chalino on February 13, 2010, 03:24:45 AM

I would like to know as well. Mines is not working either.

Title: Which sensor send the temp to my Dash?
Post by: nicknikolovski on February 13, 2010, 05:21:18 AM

Ok, as you know by the diagram above, the intake manifold covers both the coolant temp sensors. You may have to remove the intake for better access. Have a look behind the oil filter cover and you will see the sensors.

To test the gauge sender. Disconnect the sensor connector, get a little split pin and place it across the connector terminals (2 pins - brown/violet wire & brown/yellow wire).
This will emulate a high engine temp. Place the ignition to on position. If the gauge has moved up, the sensor is faulty. If the gauge still hasn't moved, then there is a wiring problem (open circuit) (Trace back from the sensor to the instrument cluster) and/or the gauge is faulty.

Also another simple thing I would check is your thermostat. Some thermostats that are stuck open will allow coolant to flow all the time and not let the engine warm up.

Title: Which sensor send the temp to my Dash?
Post by: JHZR2 on February 13, 2010, 11:28:25 AM

Thanks, though that was how it was laid out...  Just a few more ?s.  

Do both sensors have the same scale (same resistance readings at various temperatures?

Can either, and preferably the gauge sensor, be checked/harness removed without removing the intake?

Is the nut that connects the gauge to the pcb in the cluster part of a ground path?  There are two pins on the gauge that touch the pcb, if the threaded item is truly a ground, I may try to re-ground it by adding another wire directly.  I've tightened the nut down well with no improvement...

Title: Which sensor send the temp to my Dash?
Post by: Chalino on February 13, 2010, 02:21:45 PM

Someone please clarify which sensor should have the 2-pin connector; temp sender or temp sensor for ECU?

Title: Which sensor send the temp to my Dash?
Post by: 1991 E30 M42 on February 13, 2010, 02:56:13 PM

the 2 pin goes to the ecu and the 1 pin goes to the cluster

Title: Which sensor send the temp to my Dash?
Post by: JHZR2 on February 13, 2010, 03:14:26 PM

Yeah 2 pin brown for cluster, three pin blue for the ecu.

Are the harnesses or actual sensors accessible (not removable) with the intake and everything still attached?

Title: Which sensor send the temp to my Dash?
Post by: nicknikolovski on February 13, 2010, 06:40:01 PM

Have a look past the oil filter and you will see. If you can't get you hand in there, then remove the intake - not a difficult job.

Title: Which sensor send the temp to my Dash?
Post by: Chalino on February 14, 2010, 01:49:16 AM

Quote from: 1991 E30 M42;87422

the 2 pin goes to the ecu and the 1 pin goes to the cluster

Quote from: JHZR2;87424

Yeah 2 pin brown for cluster, three pin blue for the ecu.

Are the harnesses or actual sensors accessible (not removable) with the intake and everything still attached?

thanks guys; gonna test the sender tomorrow...

Title: Which sensor send the temp to my Dash?
Post by: 1991 E30 M42 on February 14, 2010, 09:44:20 PM

you can remove them without removing the manifold, it is difficult but it can be done