How To Install a Turbo Timer – Honda Accord

How To Install a Turbo Timer – Honda Accord


The work that the turbo timer or auto timer is responsible for is a very important one in your turbocharged vehicle. Whether you have an expensive turbo kit with a brand name turbocharger or a budget minded enthusiast, installing a turbo timer is a must for turbo cars.

Today we’ll be installing a Apexi pen style turbo timer in a 1998 Honda Accord with a Treadstone turbocharged H22a engine swap in it. Running a low boost level of 8 psi, this car has put down 275 wheel horsepower on our 448X Dynojet chassis dynamometer.

While the install for this 1998 is very application specific, this installation procedure is the same for any 1994-2001 Honda Accord. Before beginning this install, disconnect the negative terminal to your battery to prevent any shorting or electrical issues. If you have the stock radio, now is the time to find your radio code.

We’ll begin by sourcing the power harness, the three wire pronged power connector in our turbo timer package. Take a look at the three wires presented here, and familiarize yourself with the colors and purpose of each wire.


Depending on the turbo timer of your choice, the green wire here may be red with white stripe or another color. Just remember that the Red wire is constant power, and the Blue wire is the IG2 switched power output or “ON” position.

To begin installation in our Honda Accord, open the driver side door and slide the seat as far back as humanly possible so you can access the steering column.


Lower the steering column to it’s lowest point by pulling down on the steering column tilt lever.


Next look underneath the steering column to find the three mounting screws to your steering column cover. Remove these screws using a Phillips screwdriver.


Now gently pry off the top of your steering column cover.


With the top of your steering column removed, insert your finger into the gap of the lower panel and pull the lower cover away and over your ignition lock cylinder.


Trace back the ignition harness to find the brown six plug connector that joins the ignition harness to your chassis.


Now comes the wiring section of our How To Install a Turbo Timer. Take a look at the wiring diagram below of the stock ignition harness to see what wires and color wires you will be teeing into.


The red wire for your turbo timer should go to PIN 1 on the Honda Accord ignition harness.

The blue wire goes to PIN 4 or the black wire with yellow stripe. And lastly the green wire goes to PIN 3 or the yellow wire. Now take the power harness to your turbo timer and plug it into the turbo timer control box. Most turbo timer companies share this harness design and pinout, so regardless of what turbo timer you own these three wires should be enough.

If your turbo timer is a standalone type of timer, you should be done with our How To Install a Turbo Timer article at this stage. However because the Apexi unit can output 02 voltage signals to show the user lean and rich conditions, we’ll need to tap those wires as well.

Below is the 1998-2001 Honda Accord ECU pinout, and highlighted is the C16 pin which is the front primary 02 signal. There will be wires coming out of the Apexi turbo timer control box that need to be connected.


You will be focusing on two of the wires here, the black wire for grounding your Apexi control box and the white wire which is the signal wire for the primary 02 sensor.

If you do not connect the 02 sensor wire, you MUST ground the black ground wire to a CHASSIS ground, not the ECU ground.


Connect the black wire to B10 on your Honda Accord 4cylinder ECU and the white sensor wire to C 16 on the Honda ECU. Zip everything up and you have now know How To Install a Turbo Timer in a Honda Accord!

Have any questions or comments? Let us know below!