Sharing sensors for Haltech ECU and SpeedHut Gauges

Hi guys,

Working my way along this learning curve and enjoying the process.

I am using a Haltech Elite 2000 also. I have decided that it's going to be tricky to add multiple senders, so I am trying to avoid that now.

I have purchased a set of SpeedHut Gauges (the one in question is: https://www.speedhut.com/gauge/GRM4-QUAD-01/1/Quad-Gauge---Water-Temp-Metric,-Volts,-Oil-psi,-Fuel-Level) and they were supplied with wiring and connectors for pressure & temp gauges.

1) These were supplied with a 3-wire 0.5-4.5V Oil Pressure Sender. I was going to run this with 5V sensor supply from the ECU, Signal ground to ECU, and piggyback the signal to both the gauge and an AVI on the ECU. Will this work fine?

The gauge also has a signal +5v and signal ground. Should I ignore the +5, and connect the gauge signal ground to ECU signal ground?

2) I also have a 2-Wire (230-33Ohm, 140-280deg.F) Water Temperature Sender that I want to use. Can this be done as well? What is the best way to wire that to the gauge and an AVI on the ECU?

Look forward to your expertise, and sorry if it's a bit ahhh... elementary.

Heath

While it's usually possible to share sensors that provide voltage (such as most solid-state pressure sensors), resistive type sensors do not share well, and you'll need to figure out now to add separate sensors for your ECU and Gauges.

I would use the 5V supply from the Gauge for the Pressure Sender, just connect the signal to the Haltech and calibrate the Haltech to match the Gauge readings.

This is one reason folks like electronic dashes (such as Aim, AEM, MoTeC, Stack, etc) that can receive data from the ECU -- no duplication of sensors.

Sorry for the late reply, but thanks for your help on this topic, David. The style of the car does not suit an electronic dash like the ones I'm used to seeing, so that isn't an option for this install.

I'm following your advice and buying a neat little "motorsport" connector from EFI Hardware, and that should see me through.

In the case of the oil pressure sensor we talked about, would you think bridging the sender/gauge ground wire to the ECU sensor ground connection would be wise? Or just leave them isolated?

Heath

If you'd like to jump on the CAN/electronic dash bandwagon but need to keep it looking more 'authentic' check out the Freedom line from Speed Hut.

I would check with a voltmeter the voltage between the gauge ground, chassis (battery) ground, and the haltech sensor ground. As long as they were all small voltages (.1v), there is no need to connect them together.