joezmam367

86' z31 Base GLL (Digital Dash and Temp control) N/A 5spd

now that that's out of the way
I bought and have just recently been daily driving this for a week, and i know by the end of this somebody will direct me to a wiring diagram in the FSM but honestly, those diagrams are a foreign language to me and im currently making friends with an electrician to help me get them down.

as i understand it these cars have an electronic AC system with sensors and some kinda magic fans in the cabin that sense little temperature pixies and adapt the temp inside to suit you, depending on where you put the temp at on the little screen.

Mine never turns on in the morning by itself, and sometimes i cant even turn it on manually, no screen power, no lights nothing, but the clock works. However in the afternoon on my way home, at 4pm in northern FL, it runs from the time i start the car to the time i shut if off. my buttons do nothing in these instances.

So, is this the auto system working or is something most likley grounding out and turning it on without my consent?

please note, the dash did have an aftermarket radio installed that the PO removed, quite hastily by the looks of it.

care to enlighten me on how this setup actually works and what i should be seeking out and testing?

NismoPick

The wiring is very basic... it's the vacuum system that's crazy. The auto climate control is based on a network of vacuum lines and sensors. The most common problem is a vacuum leak, which will send the ACC into a fit. Check all lines. And really, the FSM is amazing.

FSM screenshot:

joezmam367

I haven't dove into the engine bay quite too far yet, but i do know from peeking around the vacuum hose that runs up to the firewall was cut, along with the other 2 that i traced back to the same pump (?) up near the pass headlight.

I have seen some people do a write up (xenonzcar i think) on referbing the heater box and that does require pulling the dash, which i was hoping to put off as i dont use AC, but it running under it's own control has me a bit irritated so it seems ill be getting into it sooner than i though.

I have downloaded and read through a lot of the FSM, i like that they give a lot of info, but the processes that it explained doing things in kind of gets me once in a while

rogerz

some possibilities. Power supply to the dash is iffy (why you have no lights). the power supplies sometimes have bad solder joints on the output wires and redoing them with a solder iron will make them better. use a 25 watt pencil gun flux and high quality electronic solder. more than 25 watt you can burn things up. You definitely need vacuum to the dash. You might be able to get it going by taking out the passenger seat and standing on your head looking up under the dash. the original system had the red line tubing coming into the dash and then teeing off right and left. if you can see the tee then run a line from the vacuum tank (it isn't a pump only turbos had that). the vac tank has one larger nozzle that goes to the cruise control one marked M that goes to the Manifold. the others go to the coolant control valve and the other goes to and thru the firewall which hooks into the cabin system. On a GLL quite likely the one to the coolant control valve has a solenoid valve on the vacuum tank for control purposes. the valve closes only with vacuum otherwise wide open all the time. I hot wired mine with a switch otherwise you get hot air all the time.

Oh yeah I forgot the grumpy part Learn to read a wiring diagram even a basket weaving major in college can do that. just follow the little lines to see where they go and what color they are. only hard part is that in Japanese L stands for blue hope you can keep that small piece of info in your head. also helps to know how electricity works. need two (2) conductors which in auto electrics means that the second conductor is usually the frame or ground as it is referred to. If you are a LImey it is called an earthing which is why Lucas is known as the Prince of Darkness.