AC/Heater Fan dead, not blowing

No, I don't think I checked that.. not sure where it is, the same compartment as the relay? I don't have a volt meter, unfortunately. The blower motor fuse (and possibly fan switch in the dash) are two things that would be within my capability at least.

should be in the same fuse box where the relay is.lid should be marked for fuse positions and relay positions on top of the lid or under it.check the fuses first before replacing anything else!

Thanks for the reply, I remember now I did pull the fuses out and check them.. they all looked OK.. except I couldn't really tell with the relay, so I bought a new relay, in case it was that. I just checked the 40W blower motor fuse again and it doesn't look blown or anything, looks normal inside. Unless you think it might be worth buying another one and trying it anyway, just to be sure. If it's not that or the relay, what should I look for next?

you really need a volt meter or a test light,and a helper to check.maybe fuse looks ok,but is not.you can buy things all day long,but until you test the things,and find the problem,you're just throwing money at it.

You're right, that would have been better from the start. I'd mostly convinced myself it was the blower motor for a couple of reasons, and was fooled. Then took out the resistor to look at & it was fairly corroded looking, so I figured a new one might do the trick. The parts online weren't all that much but I took the chance & could have saved the money, probably approached everything backwards. I know someone with volt meter who's more experienced with this sort of thing so I'll have to get hold of him at this point. Thanks again.

ok,good luck with it.i'm sure you'll find the gremlin.let me know results.

Wanted to let you know what finally happened with this. This week, right before I was going to call a mobile mechanic, I decided to check all of the fuses one more time in the cab fuse box under the dash. I actually found the #2 socket 10 AMP fuse burned out! I put a new 10 AMP in, and wouldn't you know, the fan & blower were back in action! So that whole time it was because of this fuse being blown, which for some reason I didn't catch the first time around, it was kind of hard to see. I put in a new blower motor, resistor, and relay just to find out they weren't the problem. OK.. so now I have a new gremlin to find. That fuse has blown 3 more times since I discovered the problem. Each time I replace it with another, the fan & ac work great for a time, but eventually it blows again. Is there a short somewhere? Where would I look? My owner's manual describes that fuse as being for: Daytime running lights (DRL), back up lamps, transmission, passenger air bag deactivation switch, and *blower motor relay*. Do you have any ideas what I should be looking for? Thanks!

any work done on it recently?no 4 wheeling,run over anything with under side of the truck?if it works for a while and then blows while you are driving it,you have a wire somewhere that is shorting to ground.stay away from the airbag.do you have Daytime running lights (DRL)?does it maybe blow when put in reverse?i hate to say it,but gonna have to start looking for the short.check the wires going to reverse lights switch at transmission first.let me know what/if you find it.kinda think when it blows,what you were doing,if in reverse,drl lights came on,if any,hit a bump,etc.

No work done on it recently, no 4-wheeling, didn't run over anything, no DRL lights. Will check the others things, thanks. Glad you mentioned about paying attention to what I'm doing before it happens, had that thought today too. In fact you have me wondering about when I put it in reverse.. a possibility there.. I'll let you know what happens in any case, hopefully soon.

10-4,let me know.i know you have already checked by the owners manual to make sure the 10 amp is the correct amp rating fuse that goes in that slot.

After driving the truck around this weekend, I can confirm, the #2 fuse blows when I put the truck in reverse. Where is the first place I should look? I don't know if I'll need my mechanic or not. I also read online somewhere, it could have something to do with an exposed or shorting wire in the steering column when I shift into reverse.. ? Actually I'm not sure if it blows as soon as I shift into reverse while still holding the brake on, or only when I give it gas and actually start moving in reverse. Will pay attention to that next time.

automatic or manual?which engine size?

Automatic, 2.3 L

have you tried unplugging the sensor/switch on the drivers side of the transmission,then trying new fuse,without starting the truck,just turn key to on,put it in reverse,see if the fuse blows?

I'll try that & let you know, hopefully sometime tomorrow.. Thanks.

ok.let me know.it's the neutral safety switch,with the transmission range sensor built into it.it shouldn't start with it unplugged.try that,maybe with a helper if you can.i have also seen about the wire in the shift selector rubbing the insulation off and shorting to ground and causing this.but one thing at a time!

OK I unplugged the neutral safety switch harness, turned the ignition key to on (with the blower fan running), shifted into reverse, nothing happened.. fuse didn't blow and the fan stayed on.

now plug the switch back up,and try the same thing,see what happens.

I plugged the switch back up & started the truck.. shifted into the reverse position.. the blower fan stayed on. After about 20-30 seconds, took my foot off the brake & started backing the truck up a little, a few seconds after that the fuse blew.

sounds like that switch is bad,or short in a wire that goes to it.do you see any bare places in the wires anywhere?

I'll get under the truck with a flashlight & take a good look tomorrow to see if I see anything suspect or exposed along the wire going to it. Late today, I got under the back end of the truck on the driver's side just to look at the reverse light area, and reached up into the cavity from the underside. The wiring to the bulb's socket felt sort of loose, but I wasn't sure. I also noticed a green wire with a cut end, not wired to anything. Which might mean nothing. I'm not sure if a short could be coming from the reverse/backup light wiring. When I did that test today, with the switch unplugged and putting it in reverse, would the reverse lights have still come on with the switch unplugged? Maybe I'll also get into the reverse light tomorrow to see if I find anything suspicious there. If I don't find anything with either, then I guess I should try replacing the switch? I'll let you know what I find.

check that green wire.see if it got pulled out of connector somwhere.also check the other side,see how many wires are in that connector,and the colors,you should have a yellow on this side,if you can still see what color they are.back up lights should be pink/black and black on both.one tail light should be black,brown,yellow....the other side should be black,brown,green.

That green ground wire inside the driver's side tail light compartment somehow got severed. I have no idea how, possibly from rubbing against something in there over time, who knows. I put it back together, and sure enough, that was the culprit. Everything I've been through with this problem was due to that. I first thought the blower motor had died, since for a while I thought it might be going bad because since buying the truck last year I would notice the air blowing through the vents in the cab sort of "cut out" or stop at times, for like 15-30 seconds usually, before starting to blow again. But even after putting in the new blower motor, it still did that. I was going to ask you about that issue as well.. hopefully I won't have to.. since fixing that ground wire today, not only has the #2 fuse stopped blowing but so far the air blowing through the vents hasn't stopped at times either. Well at least this has been an instructive process. Thanks for your input, it definitely helped guide me through this. Good site, glad I found it.

as soon i as read about that green wire,i knew that had to be it,but i was waiting for you to reply back about it.i don't think it's a ground wire though.all the grounds should be black.for some reason i think that green is a HOT WIRE,either for the turn signal or the tail light,but i can't remember,maybe it comes off the brake light switch.where ever you put it,leave it there,if all is working now.glad you got it done,lots of folks on here wouldn't have done what you did.the most hated thing i hate hearing on here is,WELL I'LL JUST TAKE IT TO THE DEALER!better have a big check book,shoot, i have stayed on mine for several days to find something that i missed.but this one will not go to the dealer for any reason.anyways,good work,pat your self on the back.very good trouble-shooting!!Oh,and i have a 2000 F-150 4.6L Supercab,306,500 miles...go FORDS!!!I just replaced the original fuel pump that was put in at the factory,it had the date stamped on the pump,7-24-2000!that cotton pick-en pump went 15 years and 303,500 miles.GOOD GRACIOUS OF LIFE!!!!

Thanks for saying I did good work troubleshooting, definitely encouraging to hear that! Unfortunately, didn't have a good day with it today. Back to square one. For most of the day though, the fuse didn't blow, really thought I had that one solved! What I did notice was the blower air was still cutting off at times like before, no big deal really since it doesn't stay off for very long and does blow most of the time, so you mostly keep cool still, but maybe that's a separate issue and I have no idea why.. it does it all 3 modes, a/c, max a/c, and regular fan. But again, I can live with it. Then late this afternoon, was in a store parking lot ready to leave, put it in reverse to back out, the fuse blew. I was like come on now, really?? So guess I'm back to square one. This is proving to be an annoying little gremlin. Wanted to tell you also, about that green wire, the reason I concluded it's a ground wire wasn't only because of the green color, but since the point at which it ends is screwed into the truck body, like for a ground. I guess tomorrow morning I'll get under the truck like I was planning to do yesterday and look for any exposed wire leading from the neutral switch to front of the truck. Didn't see anything suspicious going from the switch to the back end. Also starting to wonder if it could really be something shorting in the steering column. I put it into reverse kind of firmly and fast in the parking lot when it blew. What's weird, though, is it didn't blow when in reverse for quite a while since I fixed that wire yesterday and all day today, then it suddenly does. And before I fixed the wire, things had reached the point the #2 fuse would blow every single time I threw it in reverse. Wish there was a pattern that made sense here! Yeah I'm sure I'll always stick with Ford trucks though.. would really like an F-150 sometime, main thing that always kept me from getting one instead of a Ranger is the gas mileage thing, but I hear that's been improved a lot in recent years?

ok,lets stop for a minute.all the grounds on your truck and my truck are BLACK!if it's light green,it goes to the brake pedal switch,and goes to several different places,according to my haynes manual.multifunction switch,brake pedal switch,RAP module,high mount stop light,and shift lock actuator.unless the prior owner spliced a green wire into a black wire,that green wire ain't a ground wire.on machinery,green is ground,on some homes,green is ground,but on vehicles,black is ground.

I didn't know ground wires are black on vehicles, but I totally believe what you're saying. Which makes this more perplexing. It's actually a darker-green wire, pretty much like the color in house ground wires. The end of it is screwed into the truck's body inside the tail light compartment. It doesn't really look jury-rigged, it looks factory, but I can look again. I traced this wire from there to half-way under the truck so far, up to the area of the neutral switch, so it would seem original to the truck.

ok.let me do so more checking in my manual.my manual and your manual are different part numbers,but i would think the wiring should be the same.i'm gonna read for a little while,and get back to you,gonna check on the dark green wire,see where it starts and ends.HOW MANY CONNECTORS ARE IN YOUR TAIL LIGHT ASSEMBLY,SOME HAVE 2,SOME HAVE 3?see if your wires are this color.Brown=Tail lights/marker lamps Green=Left hand turn and brake light Orange or yellow=Right hand turn and brake light

OK thanks! Just wondering though, since the #2 fuse blows when I put it in reverse, and has done that BOTH before and after I fixed the severed wire, maybe the problem is coming from something else? Possibly that severed wire that grounds to the body was a separate coincidence? I'll still get under the truck to day and inspect more. Update: Here are the wires in my tail light assembly: The reverse light has a black wire going to it, and a pink & black striped wire. The tail light & brake light has a green and red striped wire, black wire, and what looks like a grey wire (or purplish grey). That green grounding wire doesn't seem to have much to do with the immediate tail light area, it just runs underneath the truck and comes up into the tail light cavity where it ends there, screwed/ grounded into the metal frame. I'm not sure what the green wire junctions with under the truck, if it's the neutral safety switch, I'd have to look again. But this is how the truck was when I bought it last year, and it only started blowing the fuse this month, so those wires would have to have an active short somewhere, if it were those. But I can't see any exposed or chaffed wire under the truck, at least what's accessible to my view.

give me some good news on your truck..

It's got me stumped. Would have loved to have been able to track this down. Looks like I'll have to pay for help at this point. Calling my mobile mechanic first, to describe what's been happening and if he has experience with electrical & locating shorts. That short must be out of view somewhere. I even took the steering wheel shrouds off to look in there, but the visible wires showed nothing suspect, including that O/D selector wire. Unless it's a faulty neutral safety switch.. but after wasting the time & money on a blower motor, resistor, and relay, don't really want to go there again. Hopefully the mechanic finds some code the computer's giving, or has a device that can pinpoint the location of the short. One thing's sure, it only does it after I shift into reverse and start backing up. If I avoid reverse, I can run the fan & a/c all day.

i'm guessing,but i think this is the problem. Neutral Safety Switch Part Number: MPE NS5579SB Product Line: Mileage Plus Electrical IMPORTANT INFO: w/ 4 Speed A/Trans $37.49 /ea or,if you have a 5 speed tranny Neutral Safety Switch Part Number: MPE NS5576SB Product Line: Mileage Plus Electrical IMPORTANT INFO: w/ 5 Speed Transmission Add to Compare $58.49 /ea

I'll make a final attempt on this. There's a good truck salvage yard not far from here I've used for years, including parts for this truck. Can probably find a lower mileage Ranger they'd take the neutral safety switch off & probably charge $15-$20 max. Looks like I'll be able to switch them out myself, studied the procedure and it looks do-able for me. Will see if that does it. If not, I'll just pay for a diagnostic or whatever, see if they can get a code read or otherwise possibly do an electrical trace to the short. Will avoid the dealer though if at all possible.

s--t!don't go to the STEALERSHIP!ask those guys at the junk yard if they have seen this before.i don't think a code reader will help on this.you ain't through yet.most everything runs through the multifunction switch,the turn signal switch,including the brake light switch,and the switch on your transmission.see how much the scrap yard wants for those parts while you are there,if you don't fix it before then.

Any luck finding your issue? I'm having the same problem on a 02 ranger. Hit a dead end at this point.