So has anyone got on hand the wiring diaframs for the main cluster and the types of signals it receives at various points? Does the speed sensor give an increase in voltage to show an increase of speed? Anyone shed some light on it for me?
Normally speedo signals are a square wave that changes frequency with speed. Have a look in the fsm. Shows a few of the signals and what to expect.
That is correct. The frequency off the square wave (according to the FSM 0.5V peak to peak square wave) will cause the speedo to work. May I ask the reason for the question? MichaelZ
biggest issue you will have is that the ecu gets its speed signal from the speedo. Even the UK company that makes a digital cluster still has the internals from a speedo fitted to an enclosure that mounts behind the replacement cluster. Went down this path when I tried grafting an R34 cluster into a 300zx housing... got everything else to work besides the speedo. Might revisit it some day, but time is an issue. Chris Summerfield/ Ezzupturbo iirc mentioned something of a signal converter that is available that allows you to adjust the signal from your speed sensor to match an alternate speedo. Unsure as to how this will work in conjunction with the ECU input signal. Might be possible, if you were to use- A. OEM speed sensor feeding 300zx speedo internals encased on an enclosure. B. Output signal of 300zx speedo sensor going to ECU and spliced into signal converter C. Signal converter adjusted to suit replacement speedo unit. Some idea of what you are contemplating might shed a little more light.
Attempting to grapht in Toyota 86 gts cluster. On further investigation I mag need to put a canbus system from the 86 into the zed to make it work. The 86 gets its speed from 4 different places I'm assuming its the wheels as there are FL, FR, RL, RR I had a quick read through your 34 cluster endouver I geusse a signal converter could work, Can you or anyone explain the fuel gauge and how it works?
Fuel gauge sender unit (in tank) is a variable resistor. Can't recall if it's ascending or descending as level drops. Range is in the fsm, under the cluster section, as is the range for oil pressure and coolant sender units
I dig full blown custom work like this (you know I do) but man you are asking for a whole WORLD of hurt
When I added this I had to set it to P4. The number of pulse signals received from the ECU to give the correct speed on digital display. It was the same setting as a 1986 Toyota (not 86) so the speedo internals must be similar. I notice that a plug from the back of my Zed speedo is not connected to the socket on the harness. Don't know why, but no one seems to suggest it should be connected whenever I mention it because my Zed speedo works as is and the digital display that connects directly to the ecu also works. I did remove my speedo from the cluster and was going to install a SAW display in it (CAM 8300zx9 suggestion) so I assumed I could drive around legally with this digital display, but I don't think I did, the speedo went back in first. (anyway it cost $50-$80 for the speedo/parking sensor kit) the circuit board just receives a pulse from the ecu, I would have thought the ecu gets it signal from the sensors or the sensors signals are combined at the cluster circuit (not speedo) and then taken as one by the ecu.
Oh I know, finally got the 86 cluster in my hands and will physically fit thankfully. Will be a challenge but end game is worth it to me if it works.
