Low Coolant Light
 

Hey All,
The latest challenge on the 1989 is to determine why the low coolant light comes on often. I have replaced the sensor that is located in the radiator twice. The light intermittently comes on and goes out regardless of speed or weather conditions. The radiator is full. Do ya think that I need to disconnect the battery to reset the computer after replacing the sensor?

Any idea gratefully accepted.

Thanks,

RE: Low Coolant Light
 

Why did ya' replace the sensor twice? Didthey test bad? Or just tryin' the ol' Fully Automatic Assault Wallet practice?[sm=shootshoot.gif][sm=violent053.gif]




If ya' just did a coolant change, ya' can get an air pocket in the system, that occasionally circulates to the sensor. When that happens, the light comes on.

After a few drive cycles, all the air get 'burped' out.

If you haven't had acoolant change (or any loss, which allowed the air in there), somethin' else is wrong... But try to find out what's wrong, instead of buyin' parts blindly. Feel free to send the money to me tho'.:D

RE: Low Coolant Light
 

Actually, this beast has done a major offensive on my wallet! Have been driving it for over a month since the antifreeze was put in. One would think that any air pockets would be purged by now.

Am not sure how to test this sensor. It has only one contact and checking it with a meter does not seem possible. Any ideas on how it should read?

Check is in the mail!

RE: Low Coolant Light
 

1st, check your "Gauges" fuse which powers the "Low Coolant" module. If the fuse is good, then most likely the module is bad. I'll have to get back to you on the location of the module and the wiring colors as there are 4 wires to it. Most likely it is behind the passenger side I/P.

RE: Low Coolant Light
 

Yeah, you'd think, but I'm guessin' NOT. Have you done highway drivin? Maybe an hour sustained? I don't know how long it takes, but I have re-worked an L98 top end, and it is convoluted indeed.

RE: Low Coolant Light
 

Light is still on and seem to stay on longer. Coolant level is good. New sensor did not help. Checked the manual and no mention of any of the relays in the fuse panel controlling the coolant level sensor light. Will have to dig in to the wiring diagram and see whats what.

Thanks,

[Deleted]
 

[Deleted by Admins]

RE: Low Coolant Light
 

Stays on longer could mean the air is comin' up as you do more drive cycles. Put your heat on max too - to flow the coolant more...

Are you checkin' level at the radiator cap, or at the reservoir?

I got haynes diagram, but I think it's for '84 CFI, and doesn't say much.... If ya' want I can post it...

RE: Low Coolant Light
 

Did you read what I had said earlier in the post about the "Low Coolant Module"? It is probably bad or has no power to it. That is what turns the light on based on input from the level sensor.

RE: Low Coolant Light
 

Thanks for the tips.

Have had little time to play with it lately but the light remains on.

Hopefully, when the weekend comes along, I will dive into it.

Drive on!