J Chen

Hi,
Right now am planning to going standalone ECU.
For those who have experience in this, would you kindly
advice on the do's & don'ts pls. I have the DME & KLR
wiring diagram but would like to seek for advice
how to properly wire up the Standalone ECU.

Thanks to all

Chris White

Use good wire, get as many colors/codes as you can and don’t use that crappy ribbed plastic loom cover.

Oh yeah, throw away the stock loom and start from scratch.

Chris White

Dr. Dynamics

I second that...

I'm currently doing mine Megasquirted. I'm drawing the wiring in order to do it from scratch. Use TXL type wiring since it is SAE approved to withstand chemicls, temp and all that.

By the way, anyone know a nice place to buy TXL wiring. (Eagleday is PRETTY expensive by the foot).

Also, VERY IMPORTANT...Draw a Wiring scetch for future troubleshooting or else you won't even remember what you did.

Duke

Good thread. Try http://www.kayjayco.com for wiring and connectors.

Markus951

Use only new conntectors and as many different colur wires as possible. I would build a whole new wire harness to be 100% sure.

What kind of management are you going to install?

J Chen

Hi Guys,
Thanks for the advice. Btw what about speedometer, rpm
engine check lights etc. Is it link to the ECU ?.
Yes I'm going with a new loom. My main concern is if anything
from instrument panel needs to be connected to the ECU.

Many thanks again Guys

sweanders

Pull the stock harness and make yourself a good pegboard with it as base. Make sure that you don't place any extensions or connections side by side since they will grow quite thick when you cover them. I have used cables, connectors and heat shrink stuff from Tyco Electronics.

Chris White

Speedo is separate
Tach has a connection by the DME in the foot well
The gauges/idiot lights are run through the 14 pin connector in front of the fire wall near the central electrics box (not to the DME)
The only catch is the boost gauge – it s run by the KLR and seems to be an odd signal type.


Chris White

Tom M'Guinn

I'm working on that. It appears to be a PWM signal.

lart951

I have one DTA stand alone for sale. Make me an offert

theedge

I used KayJayCo for all my wire. 18 gauge should be fine for most things. I didnt bother with colors, everything is in black with some power in red Its all bundled seperatly so I can tell what does what by how many wires in the bundle as well as the gauge of the wire. Only tricky one is the fuel injectors, but everything is labeled anyway.

For shielded wire you definatly want good quality. www.aircraftspruce.com has some milspec sheilded wire thats good till 150C. Two wire shielded (whats needed for knock sensor and VR sensors on our cars) is about $1USD a foot, but you pay for quality

On the red block connector in the passenger foot well (its four pins) this is the pinout. The funky spade pins for it are available from eagleday.com. Im sure the stock boost gauge can be made to work, its probably just a pulsed signal like for the tach, but I havent bothered yet. Its not much good for modded cars anyway. The tach signal is just a plain 4 cylinder tach signal, and the tach is very accurate from my testing.

Gauge Cluster Wiring (Red 4 pin block connector)
Pin 1 - White/Green - MPG Gauge
Pin 2 - Green/Black - Tach Signal
Pin 3 - Red/White - Boost Gauge
Pin 4 - Red/Green - Boost Gauge



This is the pinout of the big 14 wire connector (the block one thats by the clutch master cylinder on left hand cars). This thing handles a lot of random stuff. It has power for the ECU, coil wiring, temp sensors for the gauge cluster, oil pressure wire for the gauge cluster, turbo water temp sensor, etc.

14 Pin Wiring Harness
1 = 2.5MM2 Green = Coil Pin 1 from ECU Pin 1
2 = 2.5 Red/Blue = Power for fuel injectors from DME Relay
3 = 2.5 Red/Grey = Y's off to DME Pin 18 and 35 from DME Relay
4 = 1.0 Green/Black = O2 Sensor Heater power from DME Relay
5 = 1.0 Black/Grey = To DME Pin 20 from DME Relay 85B
6 = 0.5 Blue/White = From G on Oil Pressure Sensor
7 = 1.0 Red/Black = To DME Pin 4 from "Start" positin on ignition switch
8 = From G on Water Temp Sensor
9 = From WK on Oil Pressure Sensor
10 = From W on Water Temp Sensor
11 = From Turbo Temp Sensor
12 = Not Used
13 = From DME Pin 29 (AC Compressor +)
14 = Not Used


Speed is all self contained and provided by the transaxle sensor. Gas level is also self contained. The way Porsche did the gauge clusters is awsome, makes it a cinch to go with standalones.

theedge

Should be doable with a PIC microcontroller Could base it off this circuit as the input for the PIC, then its just a matter of figuring out the PWM. Im pretty sure PIC has some PWM built into it.

http://www.audiworld.com/tech/elec94.shtml

Tom M'Guinn

What I'd like to do is re-map the dash gauge so it reads from 0 to 25psi, using the zeitronix boost sensor. Parallax has a PWM chip that rides under its BASIC Stamp module that I'll use for now.

theedge

Ah I didnt know they had a seperate chip for that. Id suggest using that MAP sensor from the link I provided. Its good to 22PSI of boost I think, and its like an 8th of the price of the ZT sensor Its also automotive rated. Its the standard MegaSquirt sensor

Tom M'Guinn

I already have the zeitronix sensor as part of the wideband set-up, and sometimes exceed 22psi