'96 Ranger Urgent Electrical Issue

[Trevor Dean]

1995 Ranger XLT E/Cab, 3.0, 5-spd. No power doors/locks/windows/ mirrors, etc (just A/C). No issues with the truck except for the electrical problems stated below.

Last week the speedometer started becoming a little erratic. Today the needle suddenly quit registering completely. In Addition, other electrical problems occured at the same time.

What DOES still work:

Headlights (hi/lo), flash-to-pass function, parking/tail lights, A/C/fan, horn.

What QUIT WORKING when the speedo went out:

NO brake lights, no turn signals, no emergency flasher, no radio/light, no interior lights (overhead), no wipers/washers. ABS light continuously flashes (in inst cluster).

All fuses are ok, both inside the truck and under the hood.

Could this be caused by a defective turn signal switch on the column? I had somethihg similar happen to a 1990 Crown Victoria once, and the switch was the culprit. I know a lot of things are routed thru this unit.

Was jusr 30 miles from home today and decided to turn back in case things really went south. Fortunately, nothing else happened and it still runs great.

I could check out all the pins in the two t/signal plugs if I knew what each one was for, but I have no info on that.

Any assistance will be greatly appreciated.

 

[Trevor Dean]

1995 Ranger

Typing error in previous title. This is a 1995 Ranger, not a '96. Sorry

 

[adsm08]

That's quite the array of things that quit.

A number of them could be caused by the MFS, but not the radio or the speedo. Speedo could be related to the ABS light though.

My advice would be to get some good wiring diagrams and then chase the problems down one at a time. Find one, fix one, see what changes. That's the best way to deal with multiple systemic issues like that.

 

[Earl43P]

Clean up the grounds on the inner front fenders (3), the radiator support, head to wiper motor bolt and report back.

 

[97RangerXLT]

I agree with the above. Check all of your grounds, and tackle things one at a time.

AJ

 

[Trevor Dean]

Agree

I agree with tackling one item at a time in most cases. I know that most things electricak pass thru the t/signal (multi function) switch, so that's why I was thinking of starting there. The speedometer one was really puzzling though. As I said, everything went out with the speedo fluctuations.

When it was reading steady (hi-way trip @ 70 mph) all the other things worked ok. When it began dropping off, al the other things began fluctuating, as evidenced by the radio backlight. At that same time, if I tried a turn signal, the inst indicator blinked rapidly. If I tried the emer flashers, both indicators flashed rapidly. When the speedo returned to normal, al others worked ok. When the speedo needle permanently dropped to zero, all other things also quit working completely.

I'll put the t/signal unit back on today and start going after grounds. I do a lot of work on old 'muscle era' cars, so I'm quite familiar with the often- unusual effects generated by bad grounds.

I do have a Ranger shop manual, although it's one of the aftermarket ones. Never found a factory original like I have for my '64 Galaxie. Thanks for the fast replies. I'll report back later today.

 

[Trevor Dean]

Addressing Problem

Most of today I worked on 'grounds'. Prevous owner did a lot of shoddy work on this very nice truck. I've been meaning to correct things for the past two years, so this was a good 'opportunity'.

I removed all ground wires under the hood. Pos and Neg battery terminals, the ground to the radiator support (removed the stud and cleaned also), block ground, starter wires (just 'cause I was under there), the oem ground from the back of the head up to the firewall. Also r&r'd the ground wire to the inside of the top of the pass fender. All are super clean, and in some places I used Electrical cleaner (Tuner Cleaner spray). And the other end of the battery cable (Neg) that's bolted to the frame.

Nothing has changed. Everything that was not working, still is not. I'll try and get online info on testing, with my meter, several of the underhood relays in the black box mounted on the top of the driver side inner fender.

If it's not a defective relay problem, I can go the turn signal route. Other option would be remove the radio and look in/under the dash. They did some aftermarket radio installation work (shady, at best), but I thought I'd corrected all that long ago.

Everything's still a mystery; although I have pretty much eliminated firewall forward wiring.

 

[Earl43P]

You didn't mention the two grounds on the DS fender....

THESE Grounds (this is a 93, yours are in similar spots) on the DS fender.

I don't have a good photo of the right fender, but there is another one there, sounds like you did it. Pretty sure that all the lights you mentioned not working are grounded to the DS FRONT FENDER.

ABS and Brake Lights do not go through the Multifunction Switch on the column, so I don't think it's your problem.

Check the free and easy stuff first.


Yeah, some old man just used all caps to yell at you for doing all the grounds except the ones on the DS fender. LOL. I don't have 96 schematics, but I'll look at 93 and 2000 and see what jumps out as common to all those.

 

[Trevor Dean]

Posting

I apologize for being unfamiliar with posting here. Every time I try to reply, a previous message is shown, which I must delete and then type my reply. Seems a little unusual...

Anyway...I didn't see my note at the bottom of my handwritten page from todays work when typing my previous forum reply.

I did R&R one ground on the upper inside of the left fender. It has two wires fastened to it with a locking bolt, and is located next to the solenoid, as shown in your nice photo. There are not two on that particular fender on this 1995 Ranger.

I did find one additional ground when I came home and was looking over things. On the top of the firewall, directly below the pass wiper arm base is another. It's hiding behind a wire bundle that routes along the top of the firewall. Probably not the root of the problem, but I'll do it tomorrow, along with the solenoid connections. That way, all engine wiring will be in top shape going into winter.

I've been thinking more about this. There almost HAS to be one source of power for all of the "not working" components mentioned by me in the first post. I would think that not a single relay controls all of these items, so relays are not too likely suspect either. I now know how to check relays, so I'll do that tomorrow, just to eliminate them as the problem.

I did R&R a known "good" t/signal (multi-function switch), so that's out the window as the problem source. I've read mention of a "Multi-PURPOSE" switch on the steering column, but have not found anything to read about it was designed to do; only how to remove it. Chilton manuals are rather brief, to say the least. Found no info on the internet either.

On these modern (to me) Fords, could all the 'not working' items possibly route thru the ignition switch?

Eventually I may have to go behind the scenes and start looking under the dash/behind the aftermarket stereo. All this leads me to believe that 'something' has failed, or possibly a plug/connector has become disconnected.

 

[Trevor Dean]

By the way, I can still drive my Ranger in the daytime, but not after dark. When I'm coming to a stop, I just turn-on the parking lights, because they still work, and it looks like my brake lights are coming on.

For turning, I use 'hand signals', which really seem kinda funny after all these years! I'd bet there are a lot of drivers that wonder what I'm doing when I signal for a r/h turn. lol.

Sat 8.2.14 This morning, and since it takes only a few minutes time, I thought I'd check trouble codes just in case something showed up there. I plugged in the cable to the DLC and the screen was blank. Turned ign to 'run' and still a blank screen, although the truck had power and the pre-start dash indicators illuminated. Could this be related to my problem? I used this scanner only a few weeks ago and it functioned perfectly.

 

[97RangerXLT]

Another thought... check the GEM module... not 100% sure where it is but I believe it is in the dash behind the radio (or close to that area)

The GEM module could be your common denominator for all of the items that are failing...

I am not sure how to test this other than swapping it out, but I believe that it is specific to the options on your truck. so if you get one from the yard, make sure it is from a truck with the same options as yours (same engine/ transmission, 4x4, intermittant wipers, power locks/ windows etc)

AJ

 

[Trevor Dean]

Another thought... check the GEM module... not 100% sure where it is but I believe it is in the dash behind the radio (or close to that area)

The GEM module could be your common denominator for all of the items that are failing...

I am not sure how to test this other than swapping it out, but I believe that it is specific to the options on your truck. so if you get one from the yard, make sure it is from a truck with the same options as yours (same engine/ transmission, 4x4, intermittant wipers, power locks/ windows etc)

AJ

Thanks AJ. I'll look into that today too, after I find out what it is.

One of the reasons I wanted to run the scan tool this morning is because the "ABS" instrument cluster light keeps flashing. I noticed that it flashes in groups of 16, a pause, then another set of 16 flashes, and on, and on.

 

[Trevor Dean]

Gem

You may be on to something. Gereric control Module. Controls many things electronic, such as door chime warning. I didn't notice earlier but mine is not working. I just went out and turned the lights on with the door open - no chime - and it workrd the other day.

It's behind the fuse block, so THAT should be a joy to work with. Thank you. Will update later.

 

[enjr44]

You may be on to something. Gereric control Module. Controls many things electronic, such as door chime warning. I didn't notice earlier but mine is not working. I just went out and turned the lights on with the door open - no chime - and it workrd the other day.

It's behind the fuse block, so THAT should be a joy to work with. Thank you. Will update later.

That was my first guess; but, IDK, those things are a mystery to me.... There is a bunch of info on them online, just nothing seems definitive. It is like some mystery box. I think the GEM interfaces with most (don't it has anything to do with the speedo) of the functions you are having problems with. The GEM concept seems like the worst idea ever put in modern vehicles and they cost a ton.

Ed

 

[Trevor Dean]

That was my first guess; but, IDK, those things are a mystery to me.... There is a bunch of info on them online, just nothing seems definitive. It is like some mystery box. I think the GEM interfaces with most (don't it has anything to do with the speedo) of the functions you are having problems with. The GEM concept seems like the worst idea ever put in modern vehicles and they cost a ton.

Ed

I found they are also termed "General Electronic Module"

and "Central Timer Module" (by Ford Service Info).