Turbo Timer Installation

Last updated: January 12, 2000

I installed mine (HKS) with no instructions, so it is pretty straight forward. I bought the wiring harness (optional with the HKS, and highly recommended). This made it a breeze. The only difficult part was in getting to the wires and unplugging/plugging in the harnesses. --Steve


I installed a Greddy timer last weekend without the RX-7 specific wire harness. Many thanks to the two list members who were willing to disassemble their vehicles and look at where their HKS timer wires hooked into the ignition switch wires to assist me in identifying the proper wire color codes. I couldn't find any web posting for this procedure; all installation pages said use the RX-7 specific harness which was not available. For those about to undertake this project and also do not have the RX-7 specific harness, I post the wire connection procedure.

1. Connect the 12V red wire from the Greddy timer to the black wire with the green stripe on the [3] ignition harness.

2. Connect the blue ACC wire from the Greddy timer to the solid blue wire on the [3] ignition harness.

3. Connect the green ON wire from the Greddy timer to the black wire with the white stripe.

4. Connect the black wire to ground.

5. For the purple speedometer signal wire from the Greddy timer, connect it to the green with red wire on the ECU. To identify it, remove the electrical plug nearest the carpet from the ECU. This is a 22 pin plug with two rows of 11 pins, but not all slots have wires coming from them. Position the plug so the lower left slot is empty. Count the wires in the top row from the left. The 5th wire should be green with red.

Ed.'s note: This is the updated version per Martin's and Brodie Peterson's (brodie@kimber.com) revision, circa Jan 12, 2000. --Steve


Date: Sat, 08 Aug 1998 16:34:00 -0500
From: Martin Crane

The turbo timer installation says to splice into the speedometer signal wire from the ECU. That wire is green and red and located on the 22 pin plug at nearest the carpet on the ECU. This is where I installed mine and it works great. Car will move less than 2 feet before it will shut down.

Houseman, Carl W. x1323 wrote:

> The speedometer sensor is the Y/R and Y/W wires on the connector at the
> instrument cluster. These colors are maintained up through a connector
> behind the glovebox/airbag where they change to a two-wire harness
> consisting of G/B and L (blue) wires for the trip to the transmission.

Date: Wed, 6 Jan 1999 15:17:49 -0600
From: "Stover, Steve"

Maybe someone else will be interested in this Turbo Timer alternate mounting...

I originally mounted my Turbo Timer ala Mark Tsai's method using binder clips. However, I couldn't get the timer far enough to the right to see it easily for changing times or timer sequences. So I started looking for another way. In the process of nosing around, I noticed the driver's foot heater outlet vent was fairly flat on the bottom, which gave me an idea.

I got a piece of Plexiglas, I think it was, about 1/8" x 3" x 8". The place I went to had a scrap piece they gave away.

Using a propane torch, I bent this piece in the middle to about 150 degrees, about 4" on each side of the bend. The Plexiglas bracket can be attached to the bottom of the heater vent, and curves up the right side of the steering wheel column. Cut, Trim, and Rebend to your placement satisfaction. I mounted the Plexiglas to the bottom flat of the heater outlet with some, not Velcro, but it has plastic locking bristles, for lack of the proper word, made by 3M. My brother is a 3M rep, so getting the stuff was easy. Whatever is used needs to have good adhesive to withstand the hot air temps in the winter when the heater is going. I mounted the Timer the same way.

Everything is removable. The Timer is still not as high as I would like it because of harness limitations, but it is a WHOLE lot easier to see and change settings from the drivers seat.

Bending the Plexiglas is not hard, just take some time and patience - don't heat the piece too fast, and allow for cooling before moving. It was a whole lot easier than the Plexiglas I added to a cycle fairing for extra wind protection. Note that the exact placement of the bracket will be affected by the thickness of whatever is used to attach the Plexiglas to the heater vent. The 1/8" thickness is not very stiff, but my only alternative at the time was =BC", so I decided to use the 1/8" as a proof-of-concept.

Once in place it seems fine. Also, the piece developed some cracks that grew as I used alcohol to clean it in preparation for the adhesive. Next time I will clean with alcohol first, and make sure the worked edges are sanded smooth before the final wipedown. Total time is involved is mostly dependant on how picky one is about bracket fit and placement. I molded the Plexiglas with a (sharp) table saw and a belt sander.

Date: Thu, 05 Nov 1998 16:33:27 -0600
From: marc (cardmarc@concentric.net)

Rob Robbinette's web site has very clear concise instructions which I used this past weekend to wire mine. The timer instructions are near the bottom of the page. In his instructions, he talks of a 20 pin ECU. That should be CPU, which is located behind the drivers side left foot kick panel. Click on How to-- then Miscellaneous Modification of the ECU is required for installing the speedometer signal wire to pin 1M on the 22 pin ECU plug. This is the plug closest to the carpet on an installed ECU.

This afternoon I performed the GReddy Turbo Timer mod from Rob's How-To pages. Here is the text from his site:

How To Make the Stock Alarm Work With a Turbo Timer

This mod will allow the alarm system to be armed when the key is removed from the ignition with the vehicle idling using a turbo timer. Make sure you disconnect the negative cable to the battery before performing this mod.

The 20 pin connector from the car's ECU has 2 wires you need to look at, cut wire 1C (Black with Yellow) and tape up the non-ECU end (it goes to the ignition switch). Using a splice connector connect the ECU end of wire 1C into 1B (white).

I did run into a couple of hitches though. First, I have no 20-pin connector on my ECU. Of the four connectors, number one has 22-pins. 1C is not Black/Yellow, but Black/Red. Additionally, 1B is not White, but Black/White. Both of these wires are heavier then most of the others connecting to the ECU. I'm not sure what year or model vehicle the originator of the procedure had, so I made sure to cross reference everything with my service manual. 1C was infact for the ignition switch and 1B was for the main relay. Though the color codes were incorrect the actual function of the wires seem appropriate. I performed the mod by cutting 1C and spilcing the ECU end of 1C to 1B. I then tested the factory alarm using the standard alarm test. I didn't actually start the car, just turned it on until the TT kicked in and continued to run the accessories after I removed the key. I then locked the door and performed the alarm test. The system did not appear to arm when I turned the key, nor did it go off when I opened the door from the inside. Thinking that for some reason the car might actually have to be running, I started it up. I immediately experienced terrible idling problems with rpm fluctation from 1K to 3K+. I tried once more and got exactly the same result. So, at least for me this mod is bogus and could possibly be damaging. If anyone is so inclined it would be nice if you could check your service manuals and ECUs for color codes. Maybe I've been working too hard and somehow missed something. However, in the meantime I advise caution for those of you eyeing this attractive modification.


Date: Tue, 25 Aug 1998 21:06:38 -0500
From: Martin Crane

Rob's page does say ECU. It is referring to the alarm system CPU located on the drivers side of the car opposite the ECU. If you follow his instructions using this information, the mod will work as written.

>NOTE: If you use a Turbo Timer and want to still have the
> factory alarm work. The 20 pin connector from the CPU has 2
> wires you need to look at, cut wire 1C(Black with Yellow) and
> tape up end (it goes to ignition switch). Using a splice
> connector connect 1C into 1B(white). Now the alarm system can
> be set when the key is removed from the ignition with the
> vehicle idling. (Make sure you disconnect the negative cable
> to the battery first)
> This worked on my '94 perfectly.


A'pex'i's Turbo Timer Instructions and Wiring Diagram

Mark's Turbo Timer Installation Instructions

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