[Mister Nobody]

Thank you. I did just try that. No luck when the connection is made at the relay. I guess I need to work backwards from there now. I’ll be back with an update later or tomorrow

 

[Mister Nobody]

Current status is this: with the original relay in the slot - no power at the dual 15A fuses. With the other relay in the blower motor slot, power at both fuses. I had to order the relay. As previously noted, even with the good relay the blower motor still doesn’t turn on. I pulled the control board. No visual indication of burnout. I was wondering whether I could jump the switch to see if that helps but not sure how.

At the base of the fan control knob there are five pins. I have 4.9v at the 4th pin. When I crank the dial to max fan I get 3.9V at the 3rd pin. 4th pin seems to be power supply for all three knobs.

Let me know if this stokes any epiphanies. Thanks for your help.

 

[Mister Nobody]

Thanks so much for sending the manual. That's fantastic. In the meantime, a brief update: I got the new relay but it predictably did not solve the problem. I now at least have power to the fuses which is good but clearly the issue lies elsewhere. My next quest is to figure out how to bypass the on/off speed control at the board to see if it's just the switch. If you happen to know offhand whether I can jump the pin connectors with a wire to see if it springs to life, let me know. Also, as I had noted, I took a reading at the pin connectors that (I think) supply power to the fan control knob and the reading was only 4.9V - I don't know whether I am supposed to be getting more than that or not. If you know, let me know. I'm at work not and can't dig back in there until later but I will keep this thread going until I call it quits or fix it. Thanks for your support!!

 

[Mister Nobody]

No luck yet. As mentioned, I have power at the blower relay socket. However there is no continuity between any of the terminals. On the other side, where the other relay goes, there is continuity between the bottom left socket and the top socket. Should I have continuity between any of the slots in the socket?

 

[Mister Nobody]

Yeah, I understand that continuity isn't a great measure. I was only trying to make a simple direct comparison between the comparable sockets to see if there were any differences and what I saw was that there is a difference. I just don't know why. The blower motor socket has two connected wires at the back. The bottom two are power in and the top two I assume are to send the power out when the relay is engaged. The one socket shows some continuity between the top left socket and ground. The other doesn't. I was thinking that it should (both sides should have the same characteristics) but I really have no idea whether it should or should not. And if it should but does not, I'm wondering whether the failure is at the socket itself or whether it is somewhere down the line of the wire from the back. Anyway, I'm running out of ideas and might just take one more effort to disassemble the whole thing and work backwards from the blower motor.

 

[Mister Nobody]

Once you said “schematic” my eyes glazed over and I mentally raised the white flag. 😉 However in the spirit of not quitting I did indeed break the whole thing apart and work back from the blower motor. The fan controller resistor seemed like it was dead so for $18 I bought one and just installed it. The good news is that the blower is working! That’s a win. The bad news is that it only works on one speed - high. For now it’s fine but I admit to some feeling of defeat after the initial exhilaration of hearing the blower turn on. I guess the part might not be perfectly compatible or there is an issue at the controller dial on the console. But, hey, it’s a win of sorts and if nothing else I have narrowed down the problem I guess. Thank you all for your contributions. I hope this discussion will also help someone else.

 

[Mister Nobody]

Hi, in case anybody is still looking at this thread, I took another swing at fixing the blower motor. This time I have replaced everything that I can think of. I put in a new and better quality resistor. I replaced the fan in case the old one was shorting. I even temporarily installed a new climate control module to see if that would make any difference. With all of the new parts in place the fan still only blows on high. Does anybody know if there is anything else in the chain running from the controller to the fan itself that would cause the fan to only run on one speed?

 

[Mister Nobody]

Thank you. Quick question, is the connector M311 the connector that goes to the fan control amp? So the one that only has three prongs and connects directly into that amp that’s next to the gas pedal? And connector M54 is the big clip that connects into the back of the climate control module?

 

[Mister Nobody]

Thank you. Yes mine is the manual control. And I did go to the section the doc for that. Whatever is going on is not making sense to me. The fan control dial will turn the fan off and on. Beyond that it doesn’t do anything. The vent control button does work. And all of the other buttons on the climate control module work fine. I’m struggling to figure out why it would turn on to the high setting but not function to adjust the fan speed. As I mentioned, I have a second climate control module that I picked up at a junkyard and I installed that one and it was the exact same result. So I don’t think it is the climate control module. I replaced the fan. I replaced the fan control module. Seems like maybe there is something shorted in the wiring… but I’m unable to figure out how the current flows. It starts at full power. Somewhere between the dial and fan something is supposed to control the flow of current. Perhaps that is being skipped or jumped…

 

[Mister Nobody]

Ok. I had a breakthrough. I went to test the voltage at terminal 36 in the harness that plugs into the climate control module and it turns out that something is just wonky with the wire harness. If I jiggle or press the wires just right, then the blower controller works as intended. However, when I do jiggle it, it also sometimes turns off the compressor. So, basically that whole part the harness where it connects into the climate control module seems to be loose of otherwise just not right. I blasted it with some contact cleaner but that didn’t help. What the heck do I do about that? I have no idea what is on the other end of that harness nor where it goes to. Seems like a weird thing to go bad… any suggestions on how to deal with that?

 

[Mister Nobody]

Sounds awful. LOL. I was looking online to see if I can even find that harness if it comes to that but no luck. If you have any idea where I would find that, let me know. I’m somewhat hoping it’s just at the clip end. When I shake around the harness anywhere else nothing happens. It seems to be right at the clip. Worst case, I’ll check for local scrap yards.

 

[Mister Nobody]

Hey everyone. Coming back to confirm that I solved this issue. As it turns out there was a loose connection at the clip that plugs into the back of the climate control module. Actually, two loose connections: the red and blue wires on the top row of the clip on the passenger side. In order to fix this you have to remove the wires from the clip. Someone else explains this process here: Nissan 370Z Forum - View Single Post - DIY - Nav System Conversion. Note that I used a regular, but rather fine, sewing pin to press down on the release tab to get the wires out. I did not hammer anything as suggested on that link. Once I got the two wires out, I first tested them on the pins directly to see if they were indeed loose. They were. Then I used my fingernail to push up a little metal tab at the bottom of the metal female connection at the end of the wire (you'll see it) and also very gently pinched it tighter (side-to-side) with needle nose pliers. I reinserted the wires into the clip and everything works fine. Now with that done, a new blower motor, and a new resistor (or whatever it is), everything works as it should. The motor was squealing anyway - so needed to be changed. Resistor... I don't know. Maybe the sticky, squealing fan did something (heated up the wire?) to cause the connections to become loose or maybe they are unrelated. I have no idea. Anyway, it's done and with all the parts I am probably into it for about $80. Not terrible. Just tedious. Thanks for the support and good luck with any future projects.