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This isn't really about a Goldwing but it's technical in nature so I wanted to post it here. I apologize The other day, after shutting off the ignition on my car, the electric cooling fan continued to run. The car was not even close to normal operating temp yet. I know the fans can run after engine shutoff if necessary. This was not the case. I know the fan is controlled by a relay in the Constant Control Relay Module. I unhooked the battery for about 10 minutes and as soon as I reconnected it the fan started up again engine not running key not even in the ignition. This verified the relay malfunction per the troubleshooting table for the vehicle. I unhooked the battery and left it overnight resigned to the the fact that I needed to buy a new relay module. The next day I hooked the battery up to drive the car to my local dealer and order the part. The fan did not come on when I reconnected the battery! I decided to drive the vehicle a while to get it up to operating temperature it did. The fan came on when it should , went off when it should. Absolutely no problems. Shut vehicle off in garage Fan went off. Perfect. My question is, can a relay simply get "stuck" in an open/closed position and then recover after power is removed for a period of time?
 

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Still Learning
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I think more likely the thermo switch may be going out.
Most cars with the feature to have the fan run with key off and shut off after cool down, it is still the thermo switch that does that. Is there a relay involved too, not sure w/o seeing and reading/knowing the wire diagram for that vehicle.
 

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It aint rocket science
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If it is messed up it will happen again. If you are sure that is the part, replace.

JD
 

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newday777 wrote:
I think more likely the thermo switch may be going out.
Most cars with the feature to have the fan run with key off and shut off after cool down, it is still the thermo switch that does that. Is there a relay involved too, not sure w/o seeing and reading/knowing the wire diagram for that vehicle.
I should have explained the thermo switch you refer to is also in the relay module as well as several more relays. They are all contained in one box. So it would still require replacing the same part. I just don't understand why it seems to have corrected itself.
 

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The contacts will arc themselves together like a spot weld as the load is applied and removed. Especially if it is inductive like a motor for example.

The weld is kind of shitty and will often break loose from vibration of running over things, etc.

Even though cleared, the contact surface is now irregular thereby being less able to handle the current and more likely to encourage more welding or contact meltdowns.
 

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Rudy wrote:
The contacts will arc themselves together like a spot weld as the load is applied and removed. Especially if it is inductive like a motor for example.

The weld is kind of s***ty and will often break loose from vibration of running over things, etc.

Even though cleared, the contact surface is now irregular thereby being less able to handle the current and more likely to encourage more welding or contact meltdowns.
Ah the answer I was looking for ! Thanks Rudy. :thumbsup:
 

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It aint rocket science
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A friend of mine did a failure analysis for me on a headlight relay in a Ford car. He even took pictures of the contacts under a microscope.

If I remember right he blamed it on a weak spring or switching action delaying the movement of the contact causing an arc. The relay was a mini 35A and board mounted in the headlight control module.

Long and short of it is arcing and carbon build up. They do not fix themselves, just get worse.

http://www.datasheetcatalog.org/datasheet/nec/EQ1-31000S.pdf

JD







 
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