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K100RT Temperature Sensing Switch Unit Tue May 29, 2012 3:38 pm
quantech
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I was testing the voltage of the fuel pump leads and found they were dead. I then identified Fuse #6 was blown, and replaced it with another 7.5 amp fuse. When I hit the starter switch, the fuse blew again.
Later, I discovered that the Green/White wire leading to the Temperature Sensing Switch (box) #895092 was dead shorting to Ground (#9 wire from fuse #6 is shorting to brown #31 ground). I found two bad/blown diodes in the Temperature Sensing Switch Unit and replaced them with new ones and the dead short was gone... BUT when I hit the starter switch , I blew Fuse #6 and both diodes again.
I found that with the Temperature Sensing Switch (box) disconnected from the harness, I have 12v on Green/Brown (connector #15) AND Violet/Black (connector #A3). I have reviewed Bert's wonderful color-coded wiring diagrams but am wondering about the Violet and Black wire which seems to be coming from the temperature light. I do Not have the anti-theft option, and that connector is not used.
1. Where is the +12v coming from on the Violet/Black wire feeding back to the Temperature Sensing Switch Unit at the connector A3 ?
2. Is this 12+ v feed on the Violet/Black wire part of my problem leading to the dead short of the Temperature Sensing Switch Unit?
What could me causing my Temperature Sensing Switch Unit problem?
I am ready to buy a new Temperature Sensing Switch Unit but want to be sure I don't blow it too with the situation I am describing after plugging it in and hitting the starter switch. I want to be sure the Violet/Black wire is not a problem
Thanks for your review and any input you may have on my problem.
Steve
Later, I discovered that the Green/White wire leading to the Temperature Sensing Switch (box) #895092 was dead shorting to Ground (#9 wire from fuse #6 is shorting to brown #31 ground). I found two bad/blown diodes in the Temperature Sensing Switch Unit and replaced them with new ones and the dead short was gone... BUT when I hit the starter switch , I blew Fuse #6 and both diodes again.
I found that with the Temperature Sensing Switch (box) disconnected from the harness, I have 12v on Green/Brown (connector #15) AND Violet/Black (connector #A3). I have reviewed Bert's wonderful color-coded wiring diagrams but am wondering about the Violet and Black wire which seems to be coming from the temperature light. I do Not have the anti-theft option, and that connector is not used.
1. Where is the +12v coming from on the Violet/Black wire feeding back to the Temperature Sensing Switch Unit at the connector A3 ?
2. Is this 12+ v feed on the Violet/Black wire part of my problem leading to the dead short of the Temperature Sensing Switch Unit?
What could me causing my Temperature Sensing Switch Unit problem?
I am ready to buy a new Temperature Sensing Switch Unit but want to be sure I don't blow it too with the situation I am describing after plugging it in and hitting the starter switch. I want to be sure the Violet/Black wire is not a problem
Thanks for your review and any input you may have on my problem.
Steve