95 Montero tach not working
 

Where are the connections in the engine compartment of the tach wires so I can check if one came loose. Please also tell me the location of whatever the wires are connected to and any challenges reaching them. Thanks

Me Too
 

I also have a 95 Montero LS and my TAC quit working a while ago. I'm ready to dig into it as well. It worked intermittently for a while then just totally stopped. Any advice on where to start is appreciated:confused:

Im new to this board, and i'm hear for the tach issue and and ecu question. I have a 95 montero SR 3.5l 24 valve.
I been reading, but have not found a solution so far.

First, does a 1995 montero Sr support odb2. I have found 1996 listed as first year in some places and 95 listed in others.
I have never got it to talk a single word, and i have tried . even bought a Mitsubishi obd2 meter .
i've ohmed the data pin on odb2 plug to ecu, looks good a short, , but no odb2.
I am wondering if this is related to issue #2, tach does not work reliably. I replaced the orig tach, with an ebay purchase. the only time it has worked is when its cold out.

, Vin # , i'll add as soon as i find it again, it decides what is what if you have the decoder ring

thanks in advance for any help
chris

Did anyone figure this out? Sorry for the necro. I had a alternator spike voltage and mine stopped working. the Tach check plug on the fire wall shows voltage. I tried a donor cluster but no joy. My vehicle is a 01 sport.

Sure would be nice if everyone would help with these issues. A quick "How To" thread would be fantastic......How to repair/diagnose a failed tachometer.

I am restoring a few 94 Monteros, and also will need to dig into this tach issue.
https://cimg5.ibsrv.net/gimg/mitsubi...104b16175d.jpg


Here is a pic of the dash in one of my 94 Montero's:

https://cimg7.ibsrv.net/gimg/mitsubi...4d2088cb93.jpg

Fortunately I have a couple used speedo/tach clusters which might be repairable. However, I imagine the tach issue is normally a broken cable, or the drive gear at the tip of the cable.
I believe this cluster comes out pretty easy, and my shop manual details the proper procedure.

https://cimg2.ibsrv.net/gimg/mitsubi...19d373726e.jpg

Maybe some experts will reply with more information to make this thread useable to others.

Questions
 

Hey guys,

First of all, while the 95's have a data port that physically matches OBD2, it is definitely not an OBD2 compliant port. In order to interface with the system, you will need a Mitsubishi MUT2 reader (only available from Mitsubishi, as I understand, at great personal cost too).

Second, I have had the instrument clusters out of several 95's and 96's, and there is NO physical/analog tach connector, it's purely electronic. If your tach is malfunctioning, I would bet it's the guage itself. Easy to change if you have spare guage clusters.

Markroberts61.......Yep, my 94s would not connect to the obd2 scanner.....said something like "unable to establish communication...". Also, I think that all stored data is erased when the battery is disconnected......and I am using battery disconnects on all my 94s, so I guess I loose any data every time i disconnect the power. Which leads to another question.....does the computer have to "relearn" how to set the idle speed? Seems mine want to idle a bit high, and one in particular wants to idle over 2000rpm after start up.....tap the gas pedal, and it wants to idle even higher.

No tach cables.....so, maybe a broken wire, or connection pulled loose? Where is the sensor/wire that sends the signal?

Wheres the wire?
 

All of the wiring connections at the motor are under the plastic cover on top (I remove these covers and throw them away, but you are restoring, so that wont work) and the signal starts with the crank position sensor. The thing is, if that was bad, it wouldn't run, so if it is a physical wiring issue, it would be between the ECU and the tach. I think the tach itself is the weak link here. Try swapping in a spare, otherwise you'll need a fsm wiring diagram.

Mark.....Well, must be current running to the tach, and Im guessing a type of reostat that sends more current at the rpms increase? So, there should be an electrical reading at the tach where the wire feeds it. But as you say, if I have a working spare, I can plug it in and see if it works.....if not, must not be getting the power feed.

When you say "all the wiring connections are under the plastic cover on the top", do you mean the black plastic box to the right hand side of the battery in the pic below?: (Under the toothbrush):

https://cimg7.ibsrv.net/gimg/mitsubi...4f60b90cc7.jpg

By the way, mine is missing the 20A ABS fuse (center one in the pic below): The 60A ABS is there, but I wonder why the 20A slot is empty. My ABS light is on, and I was wondering if someone had removed this 20A fuse.....but now think it came this way from the factory. Any idea? If it was empty from the factory, then why is the fuse slot there?

https://cimg2.ibsrv.net/gimg/mitsubi...027b1d3766.jpg

Cover? What cover?
 

Lol!!! I see that someone has already done away with it. It covers all of those connectors on top of the intake runners. I like the look of real parts more than "beautification covers" anyway. It's kind of funny to see an engine normal since I painted mine all white to show leaks.
https://cimg8.ibsrv.net/gimg/mitsubi...66d858e7c3.jpg

Fuel rails!
 

Check em out!

https://cimg8.ibsrv.net/gimg/mitsubi...ed9e7b0007.jpg

Mark......Funny.....Ok, you meant those covers that fit on top the engine.....as you say, beautification covers.

Boy, you have a super clean engine....that white looks good, and a great color to pick up all the other wires and stuff going on.

One of those wires you zoomed in on is the Tach sending wire? Looks more like temp sending units, or fuel sniffers.......or who knows, a Flux Capactor? ha ha

I love the maintenance notes all over the engine....I have started doing the same......takes less time than pulling out maintenance records/log book and searching.

Nice welds on that shiny radiator.

Lol! Where to start?
 

Yes, those are temp sensors, the pic was showing those hot red fuel rails!

The radiator is an OSC from Rock Auto, I expected alum core and plastic tanks for $150, but this is what came! Hard to believe!

The white choice is for two reasons: first, so that any leaks show up easily. Second, to reflect more light in the engine bay for ease of work. At some point I'm going to pull everything out and paint the whole bay white. I really like it a lot!

OK.....temp sensors, and those "hot red fuel rails". I think you got something there.....all in white, making stuff easier to see, and leaks show up in a heart-beat. Tell your mechanic he better wear white gloves and not leave a spec of dirt under the hood. So often all the wires, tubes, hoses, lines, and stuff just all blend in together in that camoflauge of greasey darkness......so your idea of doing it in white is a great one.

By the way, any idea where the tach sending unit is? Is it the crank sensor, or someplace else?

Thats a superb radiator for $150....maybe they goofed and sent you the wrong one, and Richard Petty or Jay Leno is fuming mad when they got your old beater Mitsie radiator for one of their hot rods.

Radiator
 

Well, I am the mechanic and i cant let a pair of gloves come between my hands and that motor... I'll just have to wash often and keep a bottle of 409 handy, lol!!

Funny imagining the look on Leno's face getting a stock radiator, lol!

Tach signal
 

I'm certain it comes out of the ECU

ECU feeds the tach. OK, so there should be a hot wire coming from the ECU going to the tach. How do you test it for proper voltage? I guess you have to have the engine running to test?

Tach test
 

Just swap in a spare, I see you have a couple...

Don't make it more complicated than it is. I was an aircraft structure and hydraulics mechanic for 12 years, and we always, always, started with the simple stuff first. Simple stuff is cheaper, it's faster to repair, it makes you look like the guru... embrace simplicity!!!

Yep.....I have the speedo/tach cluster, and can try the "plug n play" approach. But for those reading this and who want to try to fix their tach, I was trying to cover all the angles. Hey......since you are the hydraulics engineer/mechanic, I think you need to hone up your skills by tackling all those rusty hydraulic lines on the belly of my Monty.....that will keep you at the top of your game. Ha haaaa

https://cimg9.ibsrv.net/gimg/mitsubi...da36cfa56c.png
https://cimg0.ibsrv.net/gimg/mitsubi...c89ddb247d.png
Just throwing this out there, where the pre-96 models aren't OBDII compliant, you don't need the MUT to read them.

This company in New Zealand has a software and cable combo that will read codes, and let you activate some of the "actuators" fuel pump, injectors, ABS stuff...

https://evoscan.com/

I purchased the 1.3D cable and it works! It's a little touchy, I keep having to unplug the cable to get the software to read. It also does logging!

https://evoscan.com/evoscan-gps-obdi...alogging-cable

@Marksroberts61 Do you happen to know the part number for that wiring harness that connects to the three temp senders on the water pipe? Trying to start tracking one down after discovering some horrific work by PO, and can't seem to locate that in the FSM. Thank you!

it is not OBD2 it should be OBD 1.5 1995, to my knowledge, was the only year that 1.5 existed.

So, no definitive answer on how to check to see if there is an input signal going to a tach that is not working?

Looks like alot of topics were discussed, but no clear answer regarding this.

I have a tach that has suddenly stopped and is staying at about the 2k mark.

I'm a tab late to the party but here anyway. 94 and 95 SR both have the OBDII plugs. Codes can be read with a paper clip. Plug one end into the 1 pin and the other end into the 5 pin. Turn key to start but don't start.
Check engine light will flash
Long Flash is tens
short flash is ones
so 2 long flashes and 4 short flashes would be 24 Vehicle speed sensor and so on.

11 Oxygen sensor fault. 12 Airflow sensor fault. 13 Intake air temp sensor fault. 14 Throttle position sensor (TPS) fault. 15 Idle speed control (ISC) motor position sensor fault. 21 Coolant temp sensor fault. 22 Crankshaft position (CKP) sesnor fault. 23 Camshaft position (CMP) sensor fault. 24 Vehicle speed sensor (VSS) fault. 25 Barometric (BARO) pressure sensor fault. 31 Knock sensor fault. 32 MAP sensor faulty. 36 Ignition timing adjustment signal fault. 39 Oxygen (O2) sensor fault. 41 Injector(s) fault 42 Fuel pump fault. 43 EGR fault. 44 Ignition coil (cylinders #1 & #4) fault. 52 Ignition coil (cylinders #2 & #5) fault. 53 Ignition coil (cylinders #3 & #6) fault. 55 Idle air control (IAC) valve position sensor fault. 59 Rear Oxygen (O2) sesnor fault. 61 Transaxle control module torque reduction signal fault. 62 Variable Induction control (VIC) valve position sensor fault. 71 Traction control (TC) vacuum valve solenoid fault. 72 Traction Control (TC) vent valve solenoid fault.

I am curious how the tach situation turned out? Was there any resolution to the problem?