87 Ranger V8 swap gauge questions

Bird76Mojo · Jan 30, 2018

I recently swapped a 92 Thunderbird 5.0 H.O. - AOD into my 87 Ranger. The Ranger was originally a carbed 2.0 5spd. I'm using a Ron Francis EFI harness and a Ron Francis alternator harness. So far she runs great.

BUT - I can't get the alternator to charge. It tests good. Battery Specialists told me I need to have the single pin connector wire from the alternator ran to a gauge or charge light on the dash. I have a wire on the Ron Francis alternator harness that says "alt access" on it and the instructions say it can be used to power any accessories you wish. My truck has the factory ammeter guage.

My question is, on the three connectors under the hood on the drivers side fenderwell (1 - 3pin plug, 1 4pin plug, and 1 - 8pin plug) which connector/wire runs to the ammeter gauge on my dash?

Also, which connector/wire runs to the temperature gauge? I think I'll have to pick up a Ranger sending unit for this one, but I'll figure that out later I guess.

I have a Ranger EVTM but I can't locate the pinout for all of the connectors on the fenderwell.

and because everyone loves pictures..

GB

85_Ranger4x4 · Jan 30, 2018

Beautiful truck!

Looks like C109 in my '88 EVTM

Shown in figure 2 to the left of the ignition module.

Either a yellow/white wire or a black/orange wire. They don't really do pinouts very often.

If you can point out your other ones I can try to look them up too.

Bird76Mojo · Jan 30, 2018

THANKS for the quick info! :headbang:

The only thing I have so far is in my notes that I made from my EVTM.

I have a connector listed as C102 (8pin) that has:

white/red to oil pressure indicator
red/white to coolant temperature indicator - I'll have to experiment with these and pick up a Ranger sending unit for my 5.0

On the 3 pin connector I noted the following (with a meter)

yellow/white - power at all times - I'll try running the Ron Francis alternator harness wire to this Y/W
black/yellow - power at all times
green/red - switched power start/run only

On the 4 pin connector I noted the following (with a meter)

red/gray - switched power
black/pink - I think I need to connect my AOD gear indicator connector/aftermarket relay to this to get my back-up lamps working
blue/yellow - power in run only

That's all I've been able to gather so far, and I haven't been able to make much sense of it all. lol

The truck is skimmed with filler pretty heavily I think, but that's a future project.

GB

Bird76Mojo · Jan 30, 2018

I plan on calling Ron Francis this week to inquire about their 2G alternator harness having the wire labelled as "alt acces" before I power anything up.

GB

85_Ranger4x4 · Jan 31, 2018

On mine I switched from the '86 style alternator connector to the Explorer connector (same connector, two wires were reversed) and it charges the same as it did before... and the ammeter doesn't work just the same as it did before.

One of the things on my to-do list...

It would probably be best to call them and see what the deal is, they should be able to tell you what to put to where to make it work.

Bird76Mojo · Jan 31, 2018

I called Ron Francis today but getting a tech on the phone is a rarity. I left a message and still no call-back. Typical of them in my experience.

GB

Bird76Mojo · Feb 2, 2018

Some curious findings.. My factory ammeter/battery gauge actually works. When I turn on the headlights it shows some discharge. But no matter which wire I hook my Ron Francis alternator access feed (which to my understanding wants 12v to excite the alternator field and start charging) to, it never shows that it's charging.

I have verified that the alternator charges when that single wire is hooked to 12v but it just doesn't show it on the gauge. No matter which wire I hook it to.

Hmmmm.....

GB

Bird76Mojo · Feb 2, 2018

I've tried every combination I can think of on the wires on the drivers side fenderwell. EXCEPT for grounding any of them. The alternator is charging, verified by checking voltage at the battery when running.

The factory battery gauge will show discharge but it won't show any charge.

Any ideas anyone?

GB

Bird76Mojo · Feb 3, 2018

Anyone? Beuller?

85_Ranger4x4 · Feb 3, 2018

Did it work before the swap?

If so it probably isn't the gauge at least.

Make sure you have the wiring coming back from the gauge working right is all I have. Like the BK/O wire and maybe the shunt. I need to revisit that can of worms myself, mine does nothing one way or the other.

Bird76Mojo · Feb 3, 2018

Funny you mention that. I got to thinking yesterday and when it had the 2.0 in it I don't think it ever showed anything but discharging. Just like it does now. Maybe I'll pick up another gauge just for the heck of it.

GB

Bird76Mojo · Apr 9, 2018

Still fighting this ammeter problem. The truck runs and drives flawlessly, NOW WITH A T5Z. Charges well too.

I'm currently wiring my coolant temp sender and the oil pressure sender up to the truck harness. I think I've got it nailed down, but the ammeter still needs more experimenting to get it hooked up properly.

I did have a look at the back of the gauge cluster and I didn't see the shunt. It's not apparent where it's mounted/wired in.

Still thinking about getting another ammeter gauge from the junkyard.

GB

Bird76Mojo · Apr 19, 2018

I picked up two more clusters at the junkyard for cheap. I got the coolant temp guage working, and the oil pressure guage too. The temp guage is reading high, but I suspect I ordered the wrong sender. I'm working on that now. It's been verified that the truck is running no higher than 190 at the top radiator hose connection.

Still haven't tried swapping out the ammeter just yet. Updates are coming in the next few days hopefully.

GB

Bird76Mojo · Apr 24, 2018

Anyone know where the ammeter shunt is located on an 87 Ranger 2.0 ?

GB

Bird76Mojo · May 31, 2021

It looks like I have the BK/O wire from C110 hooked directly to the positive terminal on the starter solenoid. That's also where I have the large charge wire coming from my alternator to charge the battery.

87 Ranger V8 swap gauge questions

Well-Known Member

Forum Staff Member

Well-Known Member

Well-Known Member

Forum Staff Member

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Forum Staff Member

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Sponsored Ad

Sponsored Ad

Today's birthdays

Member & Vendor Upgrades

Truck of The Month

Recently Featured

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals