Relay Driven Dual Cooling Fan Diagnostics

[@HomieHektor]

It's pretty simple if you learn to read diagrams. You we're trying so hard not to give the answer away in the beginning 😄 Great lecture guys 👍🏼

[@GoTechTraining]

Step one in learning electrical diagnosis is learning what electricity is....i think step 2 is learning to read a diagram! They are the roadmap to repair. Thanks for watching. Looks like you've made it back quite a ways :) Mike Becker, Technical Services Instructor

[@joebowin3331]

well, only about two years too late on my answer. However I was right, knew that part all along. You should remove the live off the video. I do like how clear that you made everything. You earned yourselves another subscriber. Keep up the good work. Joe

[@GoTechTraining]

Hey Joe, better late than never! Unfortunately I can't "edit" the "live" part out without taking down the whole video :( THanks for watching and subscribing! Mike Becker, Senior Technical Instructor

[@kyhomegarage3430]

you guys are great, such a clear tutorial of fan circuit function. Thank you so much.

[@GoTechTraining]

Thanks for watching Ky HomeGarage! Mike Becker, Technical Services Instructor

[@MrRealtorJim]

Help me to understand why the right (passenger's side) cooling fan is not turning on (the motor tests good) while the left (driver's side) cooling fan is working on my 2002 Toyota Camry 3.0 Liter (6 cylinder) vehicle. Could it be from one of the three fan relay switches? If so, which one? Excellent video.

[@GoTechTraining]

Hey, so the Camry's setup is very complicated. Do you have an overheating concern? It's possible that the one fan only comes on during a/c operation or when the engine is really hot. There are 3 relays and 2 fuses for this fan setup. The relays are labeled as fan relay 1-3 and the fuses are RDI(30amp) and COS(30amp). Hope this helps! Mike Becker, Senior Technical Instructor

[@MrRealtorJim]

Mike Becker, the Camry's setup is indeed complicated. You gave me hope to explore further. I was not having an overheating problem. I knew there had to be fuses somewhere to protect the fan motors. I found the COS(30 amp) fuse to be faulty. I replaced it, started the engine and the second fan came on instantly. I am so glad you responded to my post so promptly. As a D.Y.I. person I cannot thank you enough. Now I know the two fans operate independently yet in tandem.

[@robyearwood76]

Great video but you need to mention which relay number you are talking about?

[@tssalarms2626]

by the way guys,your explanation of the 2 motors in series should actually say that 2 resistors (motor windings)in series has a higher resistance so the voltage drop is greater,. the current is the same in a series circuit.

[@johncorder5353]

john corder i have a 2003 buick century, cooling fans only come on when the engine is running hot about 215 degrees. cooling fan one is suppose to run when motor is running. both fans do work, but only come on when temp goes to 215 degrees. there is power to all the relays but do not come on till the engine is hot. the temp doesn't go below the half way mark on the temp gauge. When the ac is turned on the right cooling fan is suppose to come on the keep the temp down. This doesn't happen, now the ac system may need a charge. Will this keep the system from operating correctly?

[@GoTechTraining]

Hey John, if the a/c is not properly charged it won't turn on the compressor. If the compressor doesn't turn on it probably won't turn on that fan. No reason too if the compressor isn't doing anything. As far as the other fans, as long as the vehicle isn't overheating and that temp gauge stays around half, it sounds like its working properly. Mike Becker, Senior Instructor

[@richardrussell9182]

you guys mentioned another vid where you jump relays?

[@SwayNotZay]

It’s just a ground to the pins

[@willwade1101]

I have a question about a 2001 PT Cruiser. Below the air intake in the middle of the block is a sending unit I can't Identify. It's not the coolant temp and it's not the oil pressure. I need to identify it because I broke the connector and need to replace it. Can you help?

[@salehtraboulsi1207]

I have a Chevy Impala 2002 one of cooling fans is not working ,the r one cousing the car to over heating ( one quarter) over the normal middle it doesnt goes to the max. overheating and it goes back normal again . the r not working fan we tested if the power getting there , there no power reaching the r fan ,the left one works none stop any suggestions? thank you

[@GoTechTraining]

Hey Saleh, check the engine computer for codes first of all. See if there is anything stored. From there i'd use a scan tool and attempt to command the fans on and off. Mike Becker, Senior Technical Instructor

[@neilwilliams8608]

I have an 09 charger 3.5 V6. The fuse box for the fan shows this....3 different relays with 2 different speeds for each relay. There is a large single fan hooked up. How can a single fan have 3 relays with a total of 6 different speeds? I'm thinking someone hooked up the wrong fan because, they ran a ground wire from the resistor to the fender well. Thank you in advance for your help. Thank you very much for your info in this video.

[@GoTechTraining]

Hey Neil, it's a strange setup, but accurate. The fan does have a hard ground at G102. Which could easily be the fender well. What is the issue with the fan? Mike Becker, Senior Technical Instructor

[@neilwilliams8608]

The bottom left female lead looks like it had a short because, it's black like chard. The 4 lead female harness, with 4 wires, comes up from the bottom of the battery. Someone ran a ground wire from the male resistor on the fan shroud to the fender well because, there is a short to the ground. I mean really, 6 different speeds for a single fan!? I may be a shade tree mechanic but, that doesn't make sense electrically. Thank you very much for your reply and experience.

[@GoTechTraining]

Neil, not sure where you are seeing 6 speeds. It looks to be only high and low speed for this car. Which wire is "shorted" to ground? Because pin 4, a black wire, is supposed to run directly to ground. Pin 1 is power in when the TIPM requests fan operation, pin 2 and 3 are for high/low control and relay output respectively. Mike Becker, Senior Technical Instructor

[@neilwilliams8608]

Inside the fuse box panel, it shows 3 relays for the fan. Each relay has 2 different speeds. This is what it shows under the fuse box lid. Thank you for your reply and help.

[@MattSikon]

I have a 2008 chevy equinox, my issue is when pulling into garage and putting car in park for 30 seconds or so sometimes both my radiator fans remain on. I did have a head gasket, radiator and water pump replaced recently and all repairs according to mechanic look to be good and fluids are fine as well as temps. I'm guessing hoping this may be one of the three relays, does anyone have a any guesses on this one?

[@GoTechTraining]

Matteeo, are you sure this isn't just normal operation? Mike Becker, Senior Technical Instructor

[@MattSikon]

@@GoTechTraining Honestly I'm not but it would happen randomly so I was wondering if this is a problem?

[@W.Khairi]

Great Job Guys, Thanks a lot.

[@GoTechTraining]

Thanks for watching W .Khairi Mike Becker, Technical Services Instructor

[@yanierolivera4678]

Its not the amperage in a series circuit that makes the fans turn at a lower speed, its the voltage. If both loads, of equal resistance are wired in series, then both loads must drop the same amount of voltage. If fan number 2 were to be slightly seized, it would take more amps for it to turn, yet that same amount of amperage would be passing through fan 1 without making it turn any faster because now you would have a greater voltage drop in fan 2.

[@SeusankerKissoon]

We need some more volume

[@KP-sg6hu]

tech B will be correct.

[@bigasautorepair2382]

Tech b is correct

[@GoTechTraining]

You're correct! Send me an email with your shirt size and mailing address and I'll send you out a t-shirt!. Email me @ [e-mail]

[@donniecarlisle2296]

B

[@joebowin3331]

Tech. B