Thread: Dancing temp needle (video)

It's been years, but last time I checked Courtesy Nissan did not show proper Nissan part numbers, and Greg V. could not look up parts with them. Has that changed?

My understanding was that Courtesy Parts used SKU numbers, but I believe if you look at the illustrations you might be able to see part numbers? Not entirely sure!

Here is Storm's needed part.

Also, to the OP and to future readers who may find this helpful:

The Part number for the.....

Nissan FAST term: "Sensor - Temperature" / "Temperature Sensor, with Gauge"
General used term: "Temperature Sending Unit"/ "Coolant Temperature Sending Unit"
FSM term: "Thermal Transmitter"

.....is 25080-89907. The reason is does not show up in the FAST program under the SR20DE SE-R (1997) is because it shares the same sensor as the same MY GA16DE. They don't list it twice. It is the same sensor for both engines, as verified by the Factory Service Manual (FSM) and the Nissan Master Parts Book.

Now, as mentioned above by Ben and others, the connection may well be the issue. If the harness connector has continuity at the end of the plug and the connector is tight on the sensor, then the sensor is the problem. There can be two problems with the sensor. They are: 1) The spade connector is loose (Cliff Mentioned this) or it is broken (at the metal part) and about to fall off. 2) The sensor is worn out or fatigued (rare occurence if using an OEM part). In order to test for the last two items (sensor problem/not harness problem) all you need is about 5 minutes and a multi-meter/ohm meter.

1) Set you multi-meter up to read "ohms" under 200.

2) Warm up car and disconnect the harness plug from the back of the "Temperature Sending unit". Wait for the fans to kick on (which indicates the coolant has reached 100*C or 212*F on OEM unmodified ECU).

2) As soon as the fans kick on touch the red lead to the back (metal part) of the spade connector on the "sensor" itself. Then touch the black lead to your intake manifold ground or another clean ground.

Multi-meter lead placement reference picture:



3) For a 1997 200sx @ 100*C/212*F, the reading should fall between 21-24 ohms. If it falls outside of that range, replace the sensor!

* Note * The reading may very well be different for other cars/MY's. To be certain, check the FSM for your specific engine/MY vehicle.

Thermal Transmitter ohm measurement reference: FSM for 1997 Sentra/200sx, EL section, page 95

Water temp.: 60*C/140*F = 70-90 ohm
Water temp.: 100*C/212*F = 21-24 ohm


Also, the thermal transmitter/temperature sending unit is not connected to the ECM/ECU. It is only connected to the gauge cluster, therefore it does not affect performance. The Engine Coolant Temperature Sensor (CTS) does affect general performance of the engine as it IS connected to the ECM/ECU.

Hopefully this thread can help somebody out in the future.

Ok, so is this part SENSOR-TEMPERATURE - Sentra / 200SX (B14U) 1995-1999 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com

The same as this? Buy BWD/Intermotor Coolant Temperature Sensor WT707 at Advance Auto Parts

The one at Advance auto parts is $9 cheaper, but if it's inferior I'll go with OEM.

Do you guys think the Nissan parts dealer will let me return that $40 wrong part? I have no idea

They should let you return the part, yes.

Both of those parts are the same damn inferior part you have in your car right now. They will fail in the same way in the future. I can see you're ignoring my advice to simply attach your current female spade connector to the temp sensor stub, so I'll stop recommending that.

Get the OEM piece for only $9 more.

a bad ground will also cause the temp gauge to dance around like that

???????? I'm not ignoring anything. It's 22 degrees outside and I have no garage.

Sorry, seemed like you were still hunting for a new sensor before diagnosing, or seeing if the easy/ghetto fix would work. No big deal if that's what you want to do. I prefer to give relevant advice. I assumed the ghetto fix was off the table, so I was helping you pick a new sensor.

Cheers!

Hey man my moms altima was doing the same thing and then it just stopped working completely. Where is the temp sender located on these altimas she has a 95.

Idk if its the same on the 1st gens, but on the 2nd gen, its really easy to get to. Its right on the water outlet neck (the one closest to the alternator). If it's the same, you can't miss it, theres just one little wire riveted on there. I would think its the same tho since they both have the ka24 in them.

Thanks man I'll check it when I get home. My mom is worried now cause the needle does not move anymore lol she said hurry up and fix it cause she don't wanna overheat and blow up.