Coolant level float contacts.....

[JD525IA]

I did PM Shogun about this already, but check this out:

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My float on my sensor broke off, and got the Coolant Level message. I ordered one from BMA and put it in. I still get the message/error. I took it out again and moved it up and down while connected to the car harness. It seemed to be happy only when the float was down (this is the closed contact). When you hold it up, like the coolant was full, it opens the contact and you get the message/error. It seemed that the sensor was made opposite or wrong.

I verified this by checking out my old sensor. With the float moved toward the connector pins, open continuity. When floating up or away from the connector pins, closed continuity/contact.

I called BMA and they sent a replacement. It is the same as the first. The float moving up causes the contact to open and that makes the car think you have low coolant. Can you shed any light on this?

Thanks in advance,

JD

[bubba966]

Sounds like you got the sensor for the 535/530/540 as they've got the sensor mounted in the opposite direction from the 525's. The 525 has it in the bottom of the rad pointing up. The 535/530/540 have it in the coolant expansion tank pointing down.

525 part # is 61311384739 and the overall length of the sensor is 95mm.

540 part # is 61311378320 and is 109mm long.

[shogun]

haaaaah, you should have asked immy the guy who knows the E34 and not me

I did not know the differences between these floats, on the E32 we just have one float which is on top of the reservoir/expansion tank.
And if the float on the E32 is new and still the warning comes, usually a wire is broken, or the pins retracted inside the plug housing. I just replaced these plug housings , same on brake fluid level sensor, washwater tank sensor, coolant tank, in case of the E32 it is
10 Plug housing 61131378408

http://bmwfans.info/parts/catalog/E3...lug_terminals/

actually looks different from the drawings
fits on
http://www.pelicanparts.com/cgi-bin/...%3A%20TERMINAL

[Tiger]

I believe there is another coolant sensor on the radiator that works in conjunction to this float sensor... check bentley for info.

[JD525IA]

Well after getting the 2nd sensor in three days from BMA, I was completely frustrated. I talked to BMA after doing some searching on the internet. I asked them to get a multimeter to check the continuity on their stock. They didn't have a clue about what I was proposing.

I found the top mounted for the E34's with the tank that sits near the firewall. I thought they had sent me that one. They insist they sent the right one. I personally am convinced that their supplier is making them wrong, at least for the 1992 525IA.

I got so tired of the ness that I ripped the new probe apart, removed the reed switch, measured out its distance from the neck of the probe, and soldered in a new reed switch (I happened to have one) to the opposite polarity. I put it all back together and put it in. Once I had the coolant topped off the message went away. I has been good all day today.

Sometimes you have to just take things into your own hands!

JD

[DaveVoorhis]

Ummm... Forgive me for asking the obvious, but: You have checked to make sure your car isn't upside down, yes?

[JD525IA]

Ummm... Forgive me for asking the obvious, but: You have checked to make sure your car isn't upside down, yes?

Perhaps gravity in my radiator is upside down. Sweet.

[shogun]

But then better inform BMA that something is wrong with their sensors with part number xy and what you have done to solve the problem. Not many people know as much as you and can make the mods DIY.
Saves many others a lot of trouble.

[JD525IA]

But then better inform BMA that something is wrong with their sensors with part number xy and what you have done to solve the problem. Not many people know as much as you and can make the mods DIY.
Saves many others a lot of trouble.

I stated that I soldered in a new reed switch with the opposite polarity (normally open instead of normally closed) and put the sensor back together. I am also going to modify the second unit they sent me and keep it. It was a $11 part and they did pick up the shipping on the 2nd one.

I told them about the problem but all they could do is say that the part # was correct for my year and model car. I even asked them if they sell many of these lately and the said they did. Yves and Patrick have some new guys answering the phone that are not quite as sharp as they are. They probably think I am just Chicken Little and crying that the sky is falling.

I got tired of beating the dead horse with them. Someone else will eventually complain again and perhaps it will get their attention. I bet they have the sensors for the 525's and the 540's mixed up and don't realize it.


I'm fixed now and happy.

JD

[uscharalph]

The replacement sensor I bought from BMA for the '89 525i never worked either. I need to get around to pulling it out and putting the old one back in. I bought a new unit when I replaced the radiator.