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Discussion Starter #1
Hi my 70 XL has a power roof, which works most of the time and is pretty cool when it does, but every now and again it stops either half way up or half way down. You can generally force it one way after that but that all depends how far its gone.
Then after a while trying to get it to go up/down it suddenly just works again. It's like there is some kind of thermal/time cutout that resets itself.
Why would it do this?
Is there anything I can do to reset it manually?
 

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if you are refering to the convertable top, there is a circuit breaker mounted on the starter relay. it could be kicking out
 

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Discussion Starter #3
if you are refering to the convertable top, there is a circuit breaker mounted on the starter relay. it could be kicking out
I'll have a look. I assume you mean the engine starter relay.
Why would it reset itself though after a certain time?
 

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I don't know anything about the convertible roof, but extech's suggestion makes sense to me and sounds like a good place to start. Some circuit breakers are self resetting, so it makes sense that it may act up some times and work fine the others. If the relay is overheating and tripping there may be some poor electrical connections that are causing the intermittent operation. Clean the connections and use some dialectric grease to help keep them clean and dry. If that doesn't work, then you'll have to go deeper. Are the roof actuators hydraulic, or electric?
 

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Discussion Starter #6
I don't know anything about the convertible roof, but extech's suggestion makes sense to me and sounds like a good place to start. Some circuit breakers are self resetting, so it makes sense that it may act up some times and work fine the others. If the relay is overheating and tripping there may be some poor electrical connections that are causing the intermittent operation. Clean the connections and use some dialectric grease to help keep them clean and dry. If that doesn't work, then you'll have to go deeper. Are the roof actuators hydraulic, or electric?
Hydraulic fluid in the motor/reservoir (it's all one piece) so, I'm guessing they're hydraulic.
I agree with extech about most cct breakers being thermal(that's how they work), but I'm used to the ones that pop out and stay out until reset.
Raining a lot over here at the moment so I'm not taking the cover off her until I can be sure of a clear enough day.
 

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I'll have a look. I assume you mean the engine starter relay.
Why would it reset itself though after a certain time?
like extech said its a thermal breaker/fuse
some will call them short stops..
once the bi-metal reaches a certain temperature it will pop up/away and break contact. once cooled off , (reset)make contact again..



corroded connectors,bad ground connections.in circuit...bad motor...etc..


will create a higher resistance/larger power draw, that generate higher temperature


so circuit breaker cuts off power before damaging motor or wires..


check/clean connectors at switch and pump motor also make sure you have a good ground at pump..


this what the circuit breaker generally looks like...


 

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um higher resistance= less current flow
correct...
less current to keep pump running at optimal speed..
like trying to get your car going in 3rd gear from dead stop...
something is gonna give...
in this case the circuit breaker...:grin2:
 

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Discussion Starter #10
like extech said its a thermal breaker/fuse
some will call them short stops..
once the bi-metal reaches a certain temperature it will pop up/away and break contact. once cooled off , (reset)make contact again..



corroded connectors,bad ground connections.in circuit...bad motor...etc..


will create a higher resistance/larger power draw, that generate higher temperature


so circuit breaker cuts off power before damaging motor or wires..


check/clean connectors at switch and pump motor also make sure you have a good ground at pump..


this what the circuit breaker generally looks like...


Ahh, there is something like that attached to the side of the start relay. Wondered what it was.
 

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looks like multiple wires on that breaker. should be protecting 1 circuit, not many
yeah i was thinking the same...


should only be the one wire that goes to convertible top switch.or..power windows and door locks ??
just dont know for sure, without a 70xl wiring schematic to look at..

if all power to ignition and headlight switch being feed thru that circuit breaker..
that would explain why it gets over loaded and cuts out..


here's a image for a 64 converible... should be very similar ...


 

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Discussion Starter #13
yeah i was thinking the same...


should only be the one wire that goes to convertible top switch.or..power windows and door locks ??
just dont know for sure, without a 70xl wiring schematic to look at..

if all power to ignition and headlight switch being feed thru that circuit breaker..
that would explain why it gets over loaded and cuts out..


here's a image for a 64 converible... should be very similar ...


Right, I'll have a look at what those extra wires are doing. (I didn't put them in, previous owners). I have a 1970 Ford workshop manual, but the wiring diagrams leave a lot to be desired, and there certainly isn't one for the power roof.
 

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Discussion Starter #14
Right, I'll have a look at what those extra wires are doing. (I didn't put them in, previous owners). I have a 1970 Ford workshop manual, but the wiring diagrams leave a lot to be desired, and there certainly isn't one for the power roof.
figured those extra wires out today, they are for the electric fan which it has installed, so only being used when the fan is in operation, which is only when the thermostat switches it on. There is also a switch to turn that same fan off completely.
None of this has been in operation when the roof has decided not to work.
Gave all the connections a good clean up while I was in there, and so far it worked fine, but it has done that before. Then just when you want it to come back up (cos it's started raining for instance, we do live in England) it stalls half way up.
So we will see what happens the next time we use it!!!
 
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