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Old 11-24-2023, 10:34 AM
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DHS928
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Default 87 windows


#15 fuse window relay bypass?

So car is running after top refresh, now issues with windows. Above is what I found when I got the car. The window relay was in, but the fuse at #15 had this fused hot wire that I am guessing bypasses the relay? Then power should go to the window switches but neither one works. They did work intermittently before I started on the refresh over a year ago.
So any good info on tracing the power to the windows. Does the wiring from the switch go straight to the window? Can I use a car battery to get the drivers window up? The pax window is up and I can drive with them both up.
Dan Serrato
Old 11-24-2023, 12:26 PM
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Alan
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Yes this is a relay bypass (not sure why). The fuse (bottom connection) goes straight to the window switch and the window switch outputs go direct to the motor. If the motors work you can move them by powering them directly - but use a fused battery supply. There are only 2 connections - so apply power to the wires one way for up and in reverse polarity for down. The window regulator worm drive and linkage can break (nylon gears) and this can then cause the motor/regulator to seize up - so that's a possible failure here - if so you will need to remove and replace the regulator - though the motor itself may well be fine still - and can be swapped between regulators (easily out of the car - difficult but possible while still mounted in the car). My GTS has suffered both sides breaking this way - so this can happen even on the newest (old) cars. You can power the motors from the switch connectors in the console - 4 way connector on each switch - use the wires on the car side [LHS: Green & Green/Red] & [RHS: Grey/Brown & Grey/Blue].

Alan
Old 11-25-2023, 09:34 PM
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Put the Fluke on the fuse plug the top blade is intermittent the lower blade slot is firm but by twisting it the window worked! Tested the relay with a battery and the Fluke it seems to be OK, the PO had one in his box of old parts, I tested it and it checked good also! I had read on the Crossfire form issues with loose fuses due to time and heat. The fix for that was to take the fuse and put a slight twist on each blade, so I tried that and it worked.
Not sure of any easy fix on the fuse receptacle, looks like you would have to pull the whole block of 11-15 to get at the plugs. I think the relays were never the problem but the PO just bypassed it with his jumper.
Old 11-26-2023, 10:58 AM
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Do you know the provenance of the fuses installed in the panel? - few of them look stock (only #21 and 2 of the spares). Contributors to fuse holder damage are typically: water leakage into the panel (or into the interior of the car), excessive fuse removals/reinsertions, incorrect items installed to fuse sockets (extra or incorrect connectors) and the use of cheap non-conformant fuses. Cheaply made Chinese fuses available in bulk at very low prices on eBay are often the cause - due to dimensional issues, poor plating materials and possibly even poor rating specs. At the very least they provide unknown (likely poor) protection against faults. The only two brands I'd recommend for use are Bussman and Littelfuse. If you aren't sure I'd swap them all out. NB #26 is the wrong rating possibly others too - check - see attached.

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CE Fuse Relay 1987-1988.pdf (348.2 KB, 17 views)
Old 11-26-2023, 11:39 AM
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Allen,

you are correct I replaced the fuses with these when I got the car, I also sprayed the sockets with NU-TROL when I put them in. They look to be of good quality, I looked them up on the web.


My replacement fuses
Old 11-26-2023, 12:06 PM
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Alan
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I'm not familiar with the brand. They are certainly not cheap - but obviously their cost is primarily driven up by the LED feature. Personally I'd still only use the 2 brands I mentioned (without the LED feature).

BTW Stabilant22 is IMO the best contact cleaner and long term contact protector - but it is very expensive, Stabilant22A is the same thing diluted with IPA - used more for cleaning than protecting. These are good for preventative measures. Removing & replacing the fuse holder blocks/terminals is the only sure fix for loose connections - but there are caveats. Each block is unique (numbered w/ fuse locations), and the internal configurations vary by year and by block range so you cannot swap any old block in. You can match the internals to what you had if you have a supply of various terminal types. Disassembly of old panels runs a significant risk of brittle parts breaking (mild heat helps), you have to remove the CE panel to refurb the fuse blocks.

Alan



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