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Repair Questions and Answers.

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 #379160  by Audacity!
 May 31st, 2019, 5:18 pm
Hello all,

I'm having an overheating issue and would be appreciative of any advice I could get on locating the problem.

So far, I've found out that the passenger side radiator fan not running should be the issue. I ran the engine until it started getting hot (3/4ths on the temperature gauge) and checked the fans. The driver's side fan was running but the passenger side wasn't moving.

I checked the passenger side fan with alligator clips and it ran when I connected it to the battery, so it appears to not need to be replaced.

With that information, what should I do next? Since one fan is working and the other isn't could it be one of the relays? All of the fuses seem to be continuous too.
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 #379162  by FIREM
 May 31st, 2019, 7:47 pm
Fans are wired in Parallel, both should be on Low or high at the same time.
99-01 3 wires for each motor. Dark Green low, Yellow high, black ground.
Under hood Power Distribution Canter Fuse E 40 amp(Low) Fuse B 30 amp ( High) Along with High & Low Relays. Low speed relay energized both fans low/ Both Relays energized High fan speed.
High speed relay only energized 1 fan only on high other fan off.
A 10 amp fuse #10 in the junction block is the control circuit for both.
Sounds like you have a low speed relay or fuse issue.
 #379770  by Audacity!
 July 12th, 2019, 9:01 am
I'm stumped. I checked the 3 fuses visually and with a multimeter and they are all good. I also got a new relay for the hi/low radiator relay. No luck. Any ideas where to go next ?
 #379796  by Audacity!
 July 14th, 2019, 8:22 pm
Since it's not the relays and fuses it must be a wire issue, right? How can I isolate which wire is the problem?

Looking at this diagram I'm guessing it's either the ground wire that goes to G101 or that dark green.
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 #379807  by hrmwrm
 July 15th, 2019, 11:20 am
probably start at the shroud plug in and check if grounds are there. plugs at the motors too.
something might not be making proper contact.
dark green is power to low speed, and yellow is high.
if one fan works, you have power.