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Defeating/Bypassing the Coolant Level Sensor?

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Old 07-31-14, 08:00 PM   #1
DanielDD
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Default Defeating/Bypassing the Coolant Level Sensor?

I just replaced my coolant reservoir with a newer used one that didn't have a coolant level sensor. It appears to be not available on the 95 and later cars. Mine is a 93 and was leaking, so this is why I replaced it. I thought I could easily disconnect the coolant level sensor and just short the connector and bypass it, but the indicator light came on anyway.

Investigation of the coolant sensor indicates a resistance reading of 8M ohm. If I invert the sensor, I get 9M ohm, so there is a 1M ohm difference between when its sensing whether there is coolant in the reservoir or not. Since I didn't readily have a 9M ohm resistor, I reconnected the sensor and inverted it and placed it in the engine compartment for the time being. I have yet to test this as its late in the evening….

I don't like the jury rig solution to defeat the low coolant light. Anybody done this in a more professional manner?
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Old 07-31-14, 09:04 PM   #2
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I'm not sure how they differ visually -- didn't know they differ at all -- but can you modify the newer one to accept the older one's sensor?
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Old 08-01-14, 08:02 AM   #3
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Quote:
Originally Posted by t2d2 View Post
I'm not sure how they differ visually -- didn't know they differ at all -- but can you modify the newer one to accept the older one's sensor?
The reason we dont really like the reserviors with the sensors, (92-94) is because they crack easily right beside the sensor. It's just a crack point. Guess where a crack is on my 92 SC? Beside the sensor.

Also I don't think one can simply drop the sensor in to the 95-up reservior.The mold that covers the hole is apart of the container.
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Old 08-01-14, 09:09 AM   #4
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I was envisioning cutting a new hole and rigging up some sort of lip for the sensor and cap. Something along the lines of a PCV Valve grommet to seal up the opening and give you something to mount to.
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Old 08-01-14, 09:21 AM   #5
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Well, for right now, I hooked the sensor back up in the inverted position and secured it next to the coolant reservoir. At least the idiot light is no longer on until I can find a more permanent solution.

A 9Meg ohm resistor should do the trick.
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Old 08-01-14, 02:20 PM   #6
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I was under the impression that zero ohms equals happy sensor. Ie. unplug it and the car will think its full. Mine is currently cracked all around the sensor so I took a plastic bag (the kind I work with is really thick like a triple thick garbage bag maybe) and covered the res with weekly refills. This is to gimp along till I can afford a new res. if I am wrong please correct me as Id like it to run right

My plan is to use a howe expansion tank instead as it's aluminum and won't crack later down the road (and cheaper too) the RX7 swaps use this with the ls1. Lol if I can find where I bought it last time I'd already have fixed it.

Anyway good luck. I currently have my sensor in the res but not connected, no lights in the dash. Although I am still chasing a hesitation problem I thought was caused by the coolant spraying my whole bay. Could be tps or maf at this point (no codes either)
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Old 09-22-14, 05:13 PM   #7
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My sensor is not connected and the light stays off. I keep it unplugged because the light is always on, regardless of the coolant level. I'm guessing this is because my sensor is bad, however I haven't verified this issue because I have more pressing things that are bugging me like brakes, shocks, trunk struts, etc.
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Old 09-22-14, 07:34 PM   #8
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subscribed because i'd like to change my ugly @$$ coolant reservoir.
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Old 09-22-14, 07:34 PM
 
 
 
 
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