Does anyone have a pic of the stock boost gauge cluster wiring

[Heggy]

I installed a stock boost gauge and a pressure switch and wired it per the TEWD (although not clear). I used a JZA70 cluster to figure out the connections for the drive circuit. I had to cut the printed circuit board so that I could make the connections (the cluster is from a N/A). I read somewhere that the boost gauge will only work under load, i.e. it won't work when the car is in neutral and stationary. is there any way to test if it is working without driving the car? If someone has a close up pic of the connections on the back of the MK3 turbo cluster it would be greatly appreciated.

Cheers

 

[tlo86]

why are you trying to get the stock boost gauge to work? from what i remember about it it barely read 9psi and took forever to read..

 

[Heggy]

At 57 8 psi is enough for me

 

[mv520]

You want a picture of the back circuit board of the cluster?

 

[Heggy]

yes please

 

[Heggy]

specifically in the area where the boost gauge connects

 

[Heggy]

Hi,

I installed a stock boost gauge and the drive circuit assembly into a N/A cluster. I also installed the 1JZ Turbo Pressure Sensor and wiring from the engine bay to the boost gauge. I hooked the 3 wires from the drive circuit black = ground, white to top connection on boost gauge and yellow to the bottom of the gauge and jumped an IGN + to this connection. The gauge does not seem to work. Any assistance would be greatly appreciated.

Cheers

 

[hvyman]

You already have 1 thread on this topic. do not make another.

 

[hvyman]

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=136

Its 3 wires.

5volt ref.
ground
signal.

have you verified that you have the correct wires?

sounds like your using the wrong sensor or your wiring is wrong.

 

[Heggy]

After some more searching I found this thread which was extremely helpful and I made the adjustments per the post (http://www.supramania.com/forums/sh...how-to-make-it-work.&highlight=cluster+wiring) actually I cut both connections on the cluster as I was looking at the rear of the JZ cluster which is opposite and upside down. I had the 2 wires reversed (thanks to the lack of information in the TEWD) on the boost gauge and had the B+ to the wrong connection on the gauge. This has been fixed, reinstalled the cluster and still no reading whatsoever. I checked the Turbo pressure sensor connector (I ran 3 wires taken from the JZA70 for the boost gauge with connectors, thru the firewall between the boost circuit on the cluster and the turbo pressure sensor in the engine bay). I stopped the engine, turned ignition back on and measured the power at the connector to the turbo pressure sensor. It is + 5VDC on both the white and orange wires. The black is ground.

Not sure what else to check....

 

[Heggy]

Yes maybe the sensor is different.... however, I checked the boost circuit PC boards (JZA70 and 7MGTE) and the components (did not validate the part number of the transistor and IC) and connections seem to be the same with the exception of the wire colors that connect to the cluster.

 

[Heggy]

I took the JZA70 Boost circuit and gauge and plugged it into the cluster connector. Gave power and ground to the gauge. It works! Don’t see any boost, but gauge springs to 0 when key is turned on and goes to -2 when engine started.
I then looked at the one installed in the cluster and it is pinned at +8 with no connector installed on the boost circuit. I will try and reverse the wires from the boost circuit to the gauge and see what happens.

 

[hvyman]

Are you sure you have the wires in the correct spot on the sensor? Power and ground might be backwards.

 

[Heggy]

I did a voltage check at the pressure sensor and the Orange and White have + 5 VDC and Brown is grounded.

some more trouble shooting : I plugged in the JZ Boost circuit and wired it to the MA70 gauge. Nothing. I reversed the connections on the gauge, nothing.

I have to assume at this point that the pressure sensor is matched to the boost gauge and boost circuit.

 

[hvyman]

Why not just put a aftermarket boost gauge in. Will be faster and more accurate.

 

[Heggy]

well mainly because I wanted to keep it looking stock, and I kind of like the look of the boost gauge in the dash. I just bought it and the boost circuit on eBay. I hope to find a press sensor.....

I did a check and the 2 press switches are different MK3 is 89420-14020 and the JZ is 89420-14040.

 

[hvyman]

Doubt it's that big of a different. But you should be able to find a used 7m one on here for pretty cheap.

 

[Heggy]

Thanks for your help, much appreciated. I'm going to wire up the gauge and boost circuit per the post and get the cluster, turbo timer hooked up and interior back together so I can drive it for a couple of months b4 winter. Hopefully I'll find a MK3 sensor and it will work : ). If not, 2015 is another year.

 

[Heggy]

Well got the boost sensor, was all excited.... still does not work...