How to make a TPS tester

tundramonkey · Jun 21, 2014

I had searched several snowmobiling sites and found some great information on how to build a TPS tester, but none of them were very detailed in how to build on. I did decide to use parts that I found on one of these posts so I cannot take credit for that.

You can find all the parts you'll need at Radio Shack:
1 ea 5VDC regulator PN# 2761770
1 ea project box PN# 2701802
1 ea 9V battery connector PN# 2700324

You will also need some wire to extend the TPS plugs from the car, a rubber grommet, heat shrink tubing, two phillips head bolts with 2 washers and 4 nuts (2 for each bolt), solder and a soldering iron and a small bolt to attach the regulator to the metal plate.

The one thing I found lacking is a plug that matches the TPS. Some just used alligator clips to connect the tester to the TPS, but this can be a difficult tasked due to the location of the TPS. I did some research and found out that Toyota cars from around 1992-96 used that same 4 pin TPS connector that is in my sled. So I went to the local junk yard and scored 3 connectors for $12 bucks.

tundramonkey · Jun 21, 2014

Preparing the project box.

1. I drilled two holes in the bottom of the box to accommodate the two phillips head bolts that I will be installing.

2. I drilled a hole in one end of the box and installed a rubber grommet that I would eventually feed the extended plug wires through.

3. I cut and bent the metal plate that comes with the project box to allow a space for the 9V battery. You will also need to drill a hole in the metal plate so you can attach the voltage regulator.

I chose phillips heads bolts for a reason. They look like a plus or positive symbol. On one of the bolts I used a hack saw to cut a negative symbol. This makes it easy to identify were the leads from your multimeter go.

tundramonkey · Jun 21, 2014

Next I extend the wires on the plug I pull off the Toyota cars. I made the wiring around 20 inches in total length. The allows the box to remain easy to get to while it's plugged into the TPS.

You only need to extend three of the wires on the plug. The wire color do not match so you have to take your time and label them so you know what wire goes to each position in the plug.

On the TPS plug in the sled the red wire is the hot wire, the black wire is the ground wire and the white wire in the return wire. I'll go over this in more detail later.

tundramonkey · Jun 21, 2014

Now to wire up the connections to the 5VDC regulator.

You need to verify what pin is "in" and which is "out" on the regulator. I found that if you place the regulator flat on the table with the pins facing to your right the pin closest to you is the "in" pin and the pin farthest from you is the "out" pin. The center pin is the ground. Again, verify this yourself.

I soldered all my connections, so prior to making the connection I tinned the wires.

The red lead from the 9V battery connector will go to the "in" pin. You will need to have a small piece of wire that you will make a butt splice with the black wire from the 9V battery connector prior to connecting to the center pin of the 5VDC regulator.

Make sure that you slide on some shrink tube prior to soldering the wires onto the regulator so it doesn't short out.

tundramonkey · Jun 21, 2014

Next feed the plug pigtail through the grommet in the end of the box so the final connections can be made.

Connect the red wire from the plug to the "out" pin of the 5VDC regulator. Connect the white wire from the plug to the positive bolt inside the project box. Connect the extra ground wire the was butt splice to the center pin to the black wire from the plug and then connect them to the negative bolt inside the project box.

I did tin the wires prior to connecting them to the bolts in the box.

tundramonkey · Jun 21, 2014

Now you can attach the 5VDC regulator to the metal plate, insert the plate in the box, connect the battery and screw on the lid. The positive and negative bolts are not connected in any way so you can leave the battery in the tester without fear of it shorting out if they come in contact with something.

tundramonkey · Jun 21, 2014

Here are a couple of picture of the TPS tester in action. The first one is at idle and the second one at WOT.

diggerdown · Jun 21, 2014

This is easier.

minet · Jun 25, 2014

not easier and way more room for error ,, those connections look like dog turd.

thanks Tundramonky for putting this together. and coming forth to share the info
i searched the site all over and no one would explain it ,, even after a direct post asking.
this guy not only showed us how but actually posted it.. others like to squirl away their knowledge so others can struggle ,, he shared it openly and even at cost and effort on his end. this forum needs more of that and less hacks and no tell nancys.

and good luck getting your ninja easy tester down into the tps prongs with the throttle bodies still in .. his is a much better design all around

Rush600guy · Mar 12, 2021

Instead of the $.33 inefficient "Linear 5v converter" (consumes 90% more energy, needs capacitors, gets HOT, and fails), it is exponentially better to trade it out and use an adjustable "Buck Converter". Less than $3 on Ebay, $5-8 for one with a digital voltmeter. Can adjust to custom voltage and recycle it into other projects.

Search

How to make a TPS tester

tundramonkey

Well-known member

tundramonkey

Well-known member

tundramonkey

Well-known member

tundramonkey

Well-known member

tundramonkey

Well-known member

tundramonkey

Well-known member

tundramonkey

Well-known member

diggerdown

Well-known member

minet

Well-known member

Rush600guy

Free Member

Similar threads