‘Where To Hook Up The Green Wire’ (For Autometer & Sunpro Tachometers):

The green wire reads the electrical pulses from the ignition. For most standard ignitions it connects to the distributor primary or negative (-) side of the ignition coil.

Do not connect to coil on MSD ignitions. Some electronic ignitions have a tach terminal on the ignition box, the green wire may connect there. Before installation read instructions. For new ignitions without distributors, contact the Auto Meter customer service department for more information.


 (Autometer Tachometer)

(Sunpro Tachometer)

Sunpro Instructions:

Green Wire Connection

The Green wire provides the tachometer with the engine RPM (speed) signal. If your vehicle’s engine is equipped with a Distributor Ignition System proceed to the Green Wire Connection – Distributor Equipped Engines section in this manualIf your vehicle’s engine is equipped with a DIS (Distributorless Ignition System) proceed to the Green Wire Connection – Distributorless Ignition System Equipped Engines section of this manual. DIS equipped engines are characterized by their lack of an ignition distributor. In place of the distributor, will be one or more “ignition coil packs”. Unlike the ignition distributor which has a basically round shape, the coil pack is typically a square or rectangular package.

Green Wire Connection – Distributor Equipped Engines:

Connect the Green wire to the negative (-) side of the ignition coil. This terminal may also be referred to as the TACH, TACH TEST, DEC, or ECU terminal. Wiring diagrams can be found in your vehicle service manual. See the list at the end of these instructions for service manual sources.

Green Wire Connection – Distributorless Ignition System Equipped Vehicles:

Many domestically built vehicles (and some imports) are now using a new type of ignition system which does not use a distributor, but instead, a system of multiple ignition coils, and the necessary sensors and computer controls to fire them in the proper order. This type of system is commonly referred to as a Distributorless Ignition System or DIS. Your tachometer is designed to work with these systems, however proper connection to them is important. The Black (ground), Red (12-14 volt supply), and White (instrument lamp) connections are the same as for distributor equipped vehicles, however connection of the Green (tach signal) wire to the ignition is specific to the engine and ignition system. Wiring diagrams can be found in your vehicle service manual. See the list at the end of these instructions for service manual sources.

Applying It To Your Vehicle:

1983 2.0L Tach test on coil (Dark Green with Yellow Stripe)
1983-1988 2.3L same as above
1983-1988 2.8 and 2.9L same as above
1989 2.3L Tach service connector (Black with Yellow Stripe)
1989 2.9L Tach test on coil (Dark Green with Yellow Stripe)
1990-1992 and some 1993 2.3L Tach service connector (Black with Yellow Stripe)
1990-1992 and some 1993 2.9L Tach test on coil (Tan with Yellow Stripe)
1990-1992 and some 1993 3.0L same as above
1990-1992 and some 1993 4.0L Tach test connector (Tan with Yellow Stripe)
1993-1994  2.3L Tach service connector (Tan with Yellow Stripe)
1993-1994 3.0L Tach test on coil (Tan with Yellow Stripe)
1993-1994 4.0L Tach service connector (Tan with Yellow Stripe)
1995 – Present You can splice into the PCM, which should be mounted on the passenger side firewall. You will need to splice into pin number 48, which will be a Tan and Yellow stripe wire, to obtain your engine RPM signal.
On 1995-97 rangers no matter which cluster you have, you do not have to put any wires through the fire wall, take your cluster out, the wide, white connector in the back of the cluster has two wires (on mine they were yellow and tan, and yellow and black) you can simply splice the green wire into the yellow and tan wire. and for the other wires you can splice into your radio. white wire can be spliced into the dimmer and the red wire can be spliced to 12 volt ignition/accessory. simply ground the black wire and you have a working tachometer. Info given was for an Autometer Phantom II mini monster that I mounted on my dash. took about maybe 45 minutes to an hour to finish including taking out and putting back the instrument cluster. just thought that this would be a helpful addition to the tach info in the library. Autometer recommends a 4 amp 3awg inline fuse for the red wire so that’s what I used for mine. lilrebelranger67 (Forum Member)
2000 — Tach service connector (DIS) or negative side of coil – Tan with Yellow stripe wire at PCM or behind cluster.

A Few Specifics:

For 1993 & 1994, Depending on the size of the motor, you can do the following:

2.3L – Off the PCM (powertrain control module) go to pin 4, which is a tan wire with a yellow stripe. Or, go to the ICM (ignition control module) and splice pin 12, which is a tan wire w/yellow stripe – this is the same for the 4.0L, too, except for the ICM connection, it will be pin 2 instead of 12.

3.0L – Off the PCM the tach signal will be pin 4, which is a white wire with a pink stripe. Or, you can go to the ICM, and splice into pin B, which will be a tan wire with a yellow stripe.

2000 Ranger:

Keyed Power = Red with Yellow stripe wire at fuse 11 or behind cluster

Dash illumination = Light Blue with Red stripe wire from radio harness or HVAC panel or behind cluster

White wire – Can be connected to the head light switch (dimmer), or to the lamps that are controlled by dimmer switch. To find the wire for dimmer from the head light switch unit, use the multimeter (voltmeter) and tap-in to the each wire until you find the wire that varies the voltage w/ the dimmer switch moved. Or you can connect to the 12V source if you do not need to dim the tachometer light.

Frequently Asked Questions From Our Forums:

Q – I have a tachometer dash. My 1st Generation tachometer doesn’t play nice with the 4.0L because of the EDIS and waste spark (or so I’m told). Will this also be a problem with aftermarket tachometers? I’m not swapping in a 2nd Generation dash. I much prefer my 1st Generation and I’ve already done all my wiring.

A – Just splice the aftermarket tachometer into the Tach Input wire off the PCM. For a 1994 4.0L it should be Tan with a Yellow stripe.

Q- My stock tachometer in my Bronco II reads considerably higher than it should with my 1994 4.0L conversion. Does anyone know if there is some sort of resistor I can add in or something else than would make it read correctly? The Tan with Yellow stripe wire in the 4.0L harness is connected to a Dark Green with Yellow stripe wire in the Bronco II harness.

A- The EDIS (and waste spark) is going to make it read wrong. 1st Generation’s didn’t have either of those. They tripped off the coil primary wire.

Q- I’m at a loss on the green wire for my 2.9. I have messed around trying to get the tachometer to read with some of the connections off the coil, but I still can’t get it running… any words of advice?

A- The green tachometer wire goes to the Dark Green wire on right side of coil. The connector has three slots for wires and on mine the green wire was closest to the engine on the connector.

Q – How hard is it going to be to install an aftermarket tachometer in a 1997 2.3L Supercab 5-speed Ranger? I read the instructions and it says something about removing the dash and connecting up to the Powertrain Control Module or something like that. It seems like an awful lot of trouble and seems like it might cause more problems than necessary.

A – Its not hard at all. The powertrain plug is located under your hood on the passenger side of the engine compartment in the rear. It is a pretty big plug – about four inches long or so. In that cluster of wires is a yellow wire with a brown stripe. that is the one I hooked my tachometer up to in my 1999 Ranger with the 2.5L.

Q – I just got an aftermarket tachometer for my 1988 ranger with a 4.0L from an 1994 Explorer. Does anyone know what wire I need to splice the green wire into? It has the coil pack with three negative wires that run to the comp. I have read that I need the tan with yellow stripe wire, but I do not have this set of wires that run to the dash. Would anyone be able to give me a hand with this one?

A – The tan and yellow wire that is being referred to is in the main harness going to the computer works like a charm.

Q – 1998 I got a Sunpro tachometer and got the power to the tachometer light to work works, but it doesn’t read rpm, it just sits on zero. I hooked up the green wire to the tan wirewith the yellow stripe running through it under the dash but its not working. Any ideas?

A – On my 1996, I tapped into a yellow with brown stripe wire next to the fuse panel under the hood. Worked perfectly.

Q – I just put a 1991 4.0L in my 1988 Bronco II. I was told that my 1988 tachometer will not work with my 4.0L signal. I am wanting to keep my 1988 tachometer I have. How do I do this?

A – I did a 4.0 conversion on my 1987 supercab last summer. The 1987 tachometer works perfectly. The tachometer wire is green/yellow, but my EVTM shows it as dark green/yellow. The wire you want to be looking to attach it to on the 4.0L wiring is tan/yellow.

Q- I have a 1996 2.3L Ranger 2WD. For the life of me I can’t seem to find the ignition wire to attach to. The manual says its a tan wire with a yellow stripe pin 48? Any help would be appreciated. 

A- You can tap into the wire coming out of the computer at the firewall (find the color and confirm pin number) OR just tap into the test tachometer terminal right on the main power distribution box in the engine bay. It has a single wire running to it.

On my 1996 and my brothers 1993, we spliced ours into the tan wire with the yellow stripe. It’s located on the drivers side right to the left of your brake or clutch pedal, under the dash. There are 2 harnesses under there. Both contain a tan wire with a yellow stripe (I spliced into the wrong one first). It’s kind of tough to find but it is there.

Q – I have a 2000 3.0L V-6 Ranger without a factory tachometer. Which wire do I splice in to?

A – Look for the DIS box under the intake manifold on the drivers side. Just splice into the yellow/tan wire coming out of the connector.


More Articles: