Was running fine...

[Crassis-Comanche]

Well friends I had a running MJ but somehow have turned it into a lawn ornament!

 

I just put in my new rad, added new fuses and started my renix tips to do list and the Comanche will not turn over. I have power to my lights, turn signals, brake lights etc. I can hear the fuel injectors up front even my door buzzer is in fine form but once I turn the key all the way over - Nothing (except that when the I turn the key over my temp gauge needle jumps and my parking brake lamp illuminates and then goes out when I release the key).

 

I have gone back over the engine bay again and checked my connections are together, my C-101 is all back together and on the fire wall and my grounds are all there - EXCEPT the braided ground to chassis wire which I removed while keeping the 4 Gauge wire from the firewall to heat shield in place.

 

Could this be my problem? Am I required to have both grounds hooked up?

 

Thanks all for any help or suggestions.

[Marine1Texas]

So the start does not click or move?

is it a Auto or a manual? could be simple as a switch not detecting the clutch in or not detecting it is in park.

Give some more info on the truck what motor as well as trans. If you have the c-101 it is either 87 or 88.

I removed my c-101 and wired everything direct.

 

That ground to chase is needed. Even make sure you clean very good, and possible upgrade it.

[Crassis-Comanche]

It's an 88 auto 4.0L 4x4.

 

I did try the column shift to see if that might be it but it's in Park. 

 

And that is correct there is no sound when I turn the key all the way over. Battery is good.

 

thanks

 

Chris

[shelbyluvv]

Remove the starter and bench test it. Or just jump the solenoid and see if it will crank. Do this with the key in the run position. Just stay clear of any moving parts.

[1989 Eliminator]

I would definatly replace the braided ground wire with a thick ground wire from firewall to engine block. Then make sure the ground post on the passenger side of the engine by the oil dipstick is CLEAN. No oil and clean contacts. It is a stud in the block so make sure that is also tight; along with the nut that goes on it.

[SBpunk]

X2 on ground.

[Crassis-Comanche]

Well I did have the nut off the dipstick ground and cleaned everything up there and reattached. Now the nut and stud are moving together and I cannot seem to separate them. It seems like I can tighten the whole thing down but it's pulling the smaller ground wires really tight and I am afraid I may break them.

 

But everything from the battery ground and the other smaller grounds, stud and nut are all turning as one unit.

 

Suggestions?

 

Thanks!

[Marine1Texas]

Did you test the starter yet? you could have a bad starter solenoid that could be completely dead or you could even have a bad starter relay. A bad relay will get you nothing no start

[FrankTheDog]

Take your ground wires off your dipstic stud.

Using an external torx tighten the stud or you can use a wrench on the fixed nut.

Now put your ground wires back on and put nut on the stud and tighten it down finger tight.

Now put the external torx on the end of the stud to hold it from spinning and tighten the nut against the grounds. It does not have to be extreamly tight.

[Crassis-Comanche]

Ok, checked the dipstick stud area again and dug out the cheap eTorx sockets and got the nut and stud apart cleaned them, cleaned the grounds and put it all back together and still having the same issue.

 

I did notice that my positive battery cable's rubber coating is badly deteriorated (down low by the starter/solenoid) like the negative one is.

 

One thing that is bugging me is the fact I have good electrical function throughout the truck. As I mentioned before all my signals, lights buzzer etc. are functioning well. But there is a strange anomaly in the dash when the turn the key to ON, my parking brake indicator lamps comes on (and goes off when I release the key) and my temperature gauge needle goes all the way to the right simultaneously (with the P. Brake lamp) and drops back down when the key is released.

 

So does this sound like a funky ground somewhere?

 

To be clear the truck fired right up after I installed the new sensors and added the upgraded gauge cluster, changed spark plugs, wires and oil change. But then...

 

I drained the coolant, pulled the rad and began cleaning the two major grounds, unplugged any connector I could find and sprayed them out with electrical contact cleaner, cleaned out the C101 and my front lighting connectors. Hooked everything back up and nada!

 

Also I am pretty sure I am in Park!  :laughin:  But I should be able to start the truck in Neutral yes?

 

Thanks all.

 

Chris

 

PS this is what my new engine to ground chassis cables looks like. It's now attached to both the firewall and engine stud (where original braided wire used to be).

 

[TheDude]

Check for battery voltage at the starter.

[Crassis-Comanche]

Ok it's been a tense week and a half but I finally followed through on the above suggestions and combined with a Hayne's manual and Cruiser's tips (more on that in a minute) I found what was causing my no start. So a huge thank you to everyone who offered a suggestion on how to diagnose what was happening with the Comanche.

 

So a friend and I figured out how to bench test the starter motor and solenoid (which were both good albeit ancient!) and I plan to replace that setup at some point. And I did replace my deteriorated positive and negative battery cables and checked my two main grounds. At that point I still had no start. I have been reading the Hayne's book and trying to teach myself to read the wiring diagrams and have some help from Youtube as well and basically tried to teach myself to use a multi-meter and then I started thinking about going back over Cruiser's Tips and sure enough I came back to this...

 

"4. Coil/ICM contacts The contacts between the coil and the ICU on your Renix Jeep can become corroded and loose causing a complete or intermittent no-start condition. I recommend the following procedure as a maintenance precaution to insure this is eliminated as a possible cause now and in the future."

 

And whaddya know! When I had originally started refreshing the grounds and cleaning contacts to get rid of the corrosion I somehow bent the metal tab inside the connector of my S Wire (to the starter solenoid) so part of it was sticking out of the connector and not making any contact with the ICU. I gently pushed the tab back inside the plastic connector and BAM! The jeep fire right up! I tested this a few times and now I am back in business.

 

Man this site and this community are AWESOME!!!  :bowdown:

 

Thanks again! Now I can get back to Project Hosehead Eh!?

 

Chris

[shelbyluvv]

Good job man! Nothing feels better than resolving a electrical issue. I tell all my friends to learn electrical trouble shooting and reading wiring diagrams. Once you have those two down most other issues are easy.