Temperatur time switch 35Cel

For all your questions, problems and DIY stories
Post Reply
User avatar
Atle_323i
E21 VIP
E21 VIP
Posts: 207
Joined: Thu Aug 16, 2018 2:00 pm
My E21(s): 76 EU 318
Location: Stavanger, Norway

Temperatur time switch 35Cel

Post by Atle_323i »

Does anyone know how much the resistor is on the temperatur time switch 35Cel for cold start injector should be?

I have 3 of theese, one brand new one which I have used in the car, and has been working just fine until recently. I'm having problems starting the car when cold.
So I replaced this with one of the 2 old I have, but they have different ohm. One has 220 ohm, and the other one has 50 ohm.
I tried with the 220 ohm unit, and the car start at once, so I guess that one is in working condition. I haven't tried the 50 ohm unit.

But can anyone tell how much the ohm should be?

50ohm unit
Image
Image

The new one, which isn't working anymore.
Image
Image

It's a German stamped Bosch unit. Are all new Bosch items so poorly made theese days?


BMW E21 318 76 ---> transforming to 323i
BMW E21 323i 79 - gone to heaven
BMW F46 220D Xdrive daily driver.
User avatar
Jeroen
Site Admin
Posts: 29804
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: Temperatur time switch 35Cel

Post by Jeroen »

It is a switch, not a temperature sender. Test instructions from the factory manual:

Image
Regards/groeten, Jeroen
User avatar
Atle_323i
E21 VIP
E21 VIP
Posts: 207
Joined: Thu Aug 16, 2018 2:00 pm
My E21(s): 76 EU 318
Location: Stavanger, Norway

Re: Temperatur time switch 35Cel

Post by Atle_323i »

Jeroen wrote: Wed May 21, 2025 10:03 pm It is a switch, not a temperature sender. Test instructions from the factory manual:

Image
Thanks, I found the chapter in my service manual, will check it out today.
But my new Bosch unit is broken, 100% sure of that. Since 1 of the pin is ground, and there is no contact through the pin to ground. I will test both my old units and see how they work. But the car starts after running the starter for about 3 seconds, not sure if that is abit long time, or is it normal when engine has cooled down over night.
BMW E21 318 76 ---> transforming to 323i
BMW E21 323i 79 - gone to heaven
BMW F46 220D Xdrive daily driver.
User avatar
nic65
Upcoming E21 fanatic
Posts: 172
Joined: Tue Sep 18, 2018 2:12 pm

Re: Temperatur time switch 35Cel

Post by nic65 »

i have one..50 ohm at 20°C....
for sale...on ebay
Post Reply