We have here a pretty darn perplexing case. We are dealing with a 1994 Montero LS with the 3.0 engine:




I just recently finished a ton of work on this rig, including replacing the head gaskets. She ran beautiful after all the work, and then she began the occasional "No Crank-No Start" issue. You turn the key, and there is only a light "click" noise somewhere in the dash, but no noise at all from the solenoid/starter. I could keep turning the key on/off trying to engage the starter, and usually after about 5 tries, the starter would engage and the engine would start right up.

So, I thought maybe the connections at the starter were getting corroded or loose, and pulled them loose and cleaned with a wire brush/sandpaper (they actually looked to be in good shape), and tightened the connections. That was of no help, so I was thinking that maybe the darn solenoid was bad. Its not much more to order the starter with the solenoid attached, so I ordered a new starter/solenoid. Installed the new starter, and I still had the same problem......No Crank, No Start, unless I kept trying 5-10 tries. Even after starting and running for a few minutes, I could turn the engine off and still have the same problem.

The Shop Manual claimed that there was a Starter Relay behind the radio, so I pulled that apart and found no relay. Turns out that the Starter Relay is only installed for the 5 speed manual trannies, not the automatics.

New Starter/Solenoid:


So I checked the shop manual again and found that the only other kink in the starting procedure could be the Park/Neutral Safety Switch.




However, it made no difference when trying to start if I tried starting in Park or Neutral, nor did it help any by wiggling the Gear Selecter as I was trying to start. Also, the Gear Selecter control was not sticking, but went from Park, Reverse, Neutral, Drive, 2, 1 with no resistance (just the typical, and the cable was not broken as the tranny changing between the gears as the gear selector was moved). So, I thought that maybe there was corrosion inside the Park/Neutral Safety Switch, and took on the challenge of removing and trying to clean it.

There is very little room to work, unless you remove the tranny fluid lines, which I was not willing to do at the time. I also tried removing the O2 Sensor, but even using my 02 sockets, it would not budge.
Pic of the Park/Neutral switch mounted on the passenger side of the tranny:
This pic was taken after the 12mm nut and locater arm was removed from the threaded shaft that goes all the way through the tranny, and attaches to the linkage on the driver's side.







After removing the nut, you are supposed to slowly wiggle the entire switch off the center shaft, and very little room to get your claws behind it to do so. I found that using a large washer, I could place it behind the switch and then sneak a long screwdriver in to pry on the left side as I tried using another paint-opener tool on the right side. I had sprayed PB Blaster on the shaft, but there was a good amount of rust on the shaft which made it like a stubborn mule to come off. Finally, it started coming off in what seemed like millionth of an inch increments. At one point I pryed a bit too hard and cracked the corner of the switch (which also probably is the cause of the broken arm on the inside of the switch which I discovered when opening it up).

Rust on shaft which made switch almost impossible to slide off:




Here is the entire switch after removing and cleaning:



Damage done from prying too hard on the old plastic/metal switch:



Inside copper connections were in good condition........but not the plastic arm:





It could be that the switch was developing a crack and all of my prying was probably the "straw that broke the camel's back".

These switches are becoming like "unobtainium", and kinda hard to find......and expensive. This was the last one at the Mitsubishi Parts Direct site, and was almost $200! Most neutral saftey switches like this cost about $50 for other vehicles.

Shaft sanded, cleaned, and greased so it will come off easy next time:



New switch installed:








I cleaned all the connectors, and used di-electric grease, and snapped all the wiring back together. Hooked the battery back up (which was fully charged), climbed back in the drivers seat and thought that the engine would start right up. Nothing has changed......still the "No Crank, No Start" issue going on. Imagine a picture of Mt. St. Helens erupting........thats how I felt at that moment. What am I missing here?

With the key "On", I put my foot on the brake pedal and moved the Shift Selector through the gears, and the dash light did light on each gear position, except Drive. For some reason the Drive light is not coming on, and I noticed this sympton around the time this starting problem started.

Does anyone have any good suggestions as to what might be the problem?
The battery terminals are clean and in excellent shape, and the ground connection is good.

To test to see if a signal was getting to the solenoid when I turned the key to "start", I removed the signal wire that attached to the solenoid, and ran a test light from it to a ground. When I turn the key to "start", the test light does come on......so that circuit must be working fine. We are getting a signal to the solenoid to crank, and I have 12.6 volts at the starter (at the end of the positive battery cable). There is a brand new Park/Neutral Safety switch, and since I am getting a good signal at the solenoid when I turn the key to "start", that tells me that the safety switch is working.

I just did a load test on the battery, and it actually went to the "Weak" yellow zone. However, after charging and using the big 200amp jump start battery charger, there is still no attempt to move the solenoid/starter when turning the key to "start". I suppose I could remove the battery and install another one, but feel that will not solve the problem. Having that "D" light not come on in the dash might be the clue to the problem.

Any suggestions?

 

Have you checked the leads coming off/to the battery for corrosion? Specifically the ground wire? Sometimes they will corrode under the sheathing and you won't even notice unless you are specifically looking for it. I had to replace mine after a no start condition and it solved the issue.

 

Naeos......Yep, the negative lead that bolts to the inner fender wall, behind the battery was removed and thoroughly wire brushed/cleaned.....but there was no corrosion there when I did this. Also, the other end of the battery posts have been cleaned, and no signs of corrosion anywhere.

Im going to pull out the battery and try another "good" battery to see if that makes a difference......I am probably wasting my time, but need to be sure. The Load Test did show the battery in the yellow "Weak" zone under load.

But you would think that the Solenoid would be making some type of "burping" sound or typical "click" noise when the key is turned to "start", but I hear nothing. The test light does show power going to the trigger wire when I hit the "start" with the key. So, doesnt this prove that the Park/Neutral Safety Switch is allowing the juice to flow from the key to the solenoid? Can I rule out problems with the Safety Switch?

Im also wondering about that "click" noise someplace in the dash, that I hear when I turn the key to "Start". This is and Auto, so there is not supposed to be a starter relay mounted behind the radio (and I did check, and found no relay there). So, what is causing that "click" noise when I turn the key to start?

Also, there is 12.6 volts at the fat positive battery cable where it connects at the starter. Thus, can we rule out any possible blown fuses?

Another thing that I forgot to mention is that now the starter absolutely refuses to crank, even after turning the key 50-100 times. Before, she would turn over and start at least by 10 tries.

Pulling my hair out on this one.

 

(Read this to the end to see a truely Bizarre starting issue)

Update on this bizarre "No Crank, No Start" issue:

1. I put another battery into the 94 Monty to verify that the battery was not the issue:

Here is the battery that I removed, and you can see clean terminals and a clean negative ground at the fender wall, and on engine:










I put another battery in and again cleaned all connections and tried to start the engine. Same results.....I turn the key to the "Start" position and get absolutely nothing from the solenoid and starter. Only a small "click" sound behind the dash. So I looked at the circuit diagram again and noticed that after the Park/Neutral Safety Switch, there was another electrical "intersection" before the circuit made its way to the solenoid/starter. It shows "2B-L" as going to the Tranny, the M. Fuel Injection, and the SRS Airbag system. I have no clue as to why this circuit is even needed for the start-up of this engine.......so, some error code in the Tranny, the Fuel Injection, or the SRS can cause a "No Crank/No Start" issue?




While sitting in the driver's seat, and trying to start after putting another battery in, I decided to again trying to wiggle the Gear Selector while turning the key......and this produced no results. Then in one of those "what the heck" moments, I reached down and pushed the Overdrive button so the Overdrive was "Off". I then turned the key to start, and the engine fired right up and started.

Now, how can this be? For some reason, the engine will only start if the Overdrive Button is "Off". I tried this several times, and it will not make any cranking sound and not start if the Overdrive Button is "On", but it will start every time if the Overdrive is in the "Off" position. The dash light also comes on showing that "Overdrive is Off".

Can anyone offer an reasons, or suggest how to fix this utterly bizarre problem?

 

It's great you are getting somewhere. It does need to trigger EFI to shoot fuel and crank the starter to start the engine. Single click may be EFI relay or fuel pump relay.

As to overdrive button, you would need to dive more into this circuit.

Is there a controller for the transmission overdrive or is it connected to the ECU?

Sometimes the ECUs of this age need capacitor replaced, when capacitor is broken results can be quite unpredictable.

I would pull the ECU or whatever the overdrive switch is supposed to be connected to, open the case and check for swollen caps.

Another theory is that the position of the OD switch somehow also cause the car to think it is not in park. A diagram about this would help.

 

OutlanderGT.......Progress is real slow, and very perplexing. Never in my wildest dreams would I have ever predicted that I could start the engine only by putting the Overdrive switch in the "Off" position.

Good point.....that single click someplace in the dash could be the EFI or fuel pump relay.....so, I can cross that one off the "problem" list.

Overdrive circuit......I need to dive into this issue and try to understand how that circuit works. I would not think that it would need permission from the ECU when the driver commands the Overdrive to be "On" or "Off"......I would hope it was a straight run from the switch down to the relay/switch on the Tranny.

Your comment about the position of the Overdrive Switch may make the car think its not in Park. Next time I will try putting the car in Neutral, then turn off the OverDrive Switch and see if the engine starts. If the Overdrive being "Off" only allows it to start in Park, then maybe you have something there.

I did try turning the OverDrive Switch to "On" after starting the engine, and the engine did not shut off. But it must be pushed back to "Off" position to crank the engine up.

I wonder if I am the first person ever to run into the bizarre situation.

Im hoping I dont need to pull out the ECU and look for swollen capacitors, but I guess its just another good learning experience.

 

StudebakerHawk, did you ever confirm your observation that EVERY single time Overdrive is ON, the engine doe2snt start, while with it OFF - it starts? Just want to know if this is a fluke or 100% reproducible condition.

 

Hunter.....That was a very good question. Yesterday, I repeated this 5-6 times........it would crank and start with OverDrive "Off", but not with it "On". But to be sure, I just went out and tried it again......first, with the OD "On", I turned the key and nothing----No Crank/No Start. Then I turned the OD "off" and turned the key, fully expecting it to start. However, this time she did not even crank/start with the OD "off". With the OD "off", it did finally crank and start after 3-4 attempts.

So, your observation/questions hit the bulls-eye......the position of the OD Switch seems to have an impact, but not 100% of the time. Back to square one here. Im wondering about that extra circuit between the Park/Neutral Safety Switch and the Solenoid/Starter. It is marked "2B-L" in the diagram above......Im wondering if there is a way to "unplug" or eliminate that part of the starting circuit? This would eliminate any starting issues caused by the "ELC 4 speed tranny, the MFI-fuel injection, and the SRS airbag system.

It is strange that my test light will come on when connected to the Solenoid, when I turn the key to "Start". If there is an error within the "2B-L" portion of the circuit, shouldnt the test light not come on when I turn the key to "start"?

 

OutlanderGTX: I took your advice and pulled out the ECM:
Behind passenger side kick panel:



The three connectors came off easy, and looked perfect.....no corrosion at all:






Remove 2 10mm nuts, and it comes right out:




Grounding wires and nut looked great too:




I had a spare ECM on hand, and was going to plug it in......but discovered that the ECM for the 3.5 engine is different than for the 3.0 engine:




3.5 engine ECM on top, and the 3.0 engine ECM on bottom......different size plugs and pin configurations:



So, I popped it open like a clam to look for those "swollen capacitors" you mentioned:




Here are some close-ups of the circuits/capacitors.......does anything "Abby-Normal" stand out at you?


















From what I can see, everything seems to look to be in great condition, considering it is almost 30 years old. Anything stand out based on your expert eyes?
Are there any "simple" tests that can be done without damaging the unit?

 

Solenoid should have power with key on start position. If it has power at all times, id think something is wrong. There might be a starter relay that feeds power to that solenoid (too much power draw to just go straight through ignition switch). I wonder if there is a relay there. Perjaps it sticks in one or both positions.
Do you have power to starter at all times?