Dead Jeep - any ideas very welcome

[UKTJ]

This morning my son needed to use my compressor to put some air in a tyre. He moved my TJ close enough to reach and switched it off.  When he next came to start the Jeep, nothing.  I went home to try and deal with it, but it is exactly as he described.

 

I did the on and off three times quickly trick, but it is showing no fault codes. Had a quick look around the engine bay but can’t see any wires that may have been dislodged.

 

One odd thing may be that when I turn the ignition to try and start the Jeep the radio / clock turns off, but comes back on when the key is turned back.  For the life of me I now can’t recall if this happened before.  I also think there is a bit of a humming, electrical sort of noise from behind the glove box when I try to start it, but again maybe this was there before and the volume of the engine started masked it.

We have pushed it out of the way as he had to get to school for an A-Level and I am now back at work.  I will be taking a look again this evening.

 

Could this be as simple as a fuse blowing?  Any other clues anyone can suggest?  Any help much appreciated.

[Cameron]

Have you tried giving the battery a boost?  The last time I had a flat battery there was enough juice to run the clock and radio but not turn over the starter.

Also, my starter motor had a lot of clay left over in it from Salsbury...it may need a good clean out.

[UKTJ]

20 minutes ago, Cameron said:

Have you tried giving the battery a boost?  The last time I had a flat battery there was enough juice to run the clock and radio but not turn over the starter.

Also, my starter motor had a lot of clay left over in it from Salsbury...it may need a good clean out.

The battery is quite new and it started first time when my son ran it initially.   I’m not even getting a click from the starter motor solenoid when I turn the key, which I think I have had with flat batteries in the past.  But I will give it a try.

 

I have moved the fuse position for starting to eliminate the need to depress the clutch, may try moving that back and / or changing that fuse.

[stewart]

whats the battery voltage ?

 

[UKTJ]

2 hours ago, stewart said:

whats the battery voltage ?

 

Just got home and checked, getting 12.7v, so not the battery.

[V]

Terry, it's not unusual to experience battery terminal electrical contact problems following the type of terrain that you have driven your Jeep through recently. My Jeep refused to start a few days ago. Dead as a Dodo, but battery at 65% charged.

 

My engine bay was probably the same colour of Wales as yours. I jetwashed it as clean as I dared to, including the alternator windings. When it had dried out in the sun I dismantled every connection to the battery. Using emery cloth I made bright all of the electrical contact surfaces. The battery terminals, inside the clamps, on the nut faces of the clamps, both sides of every washer, both sides of every tube terminal on all of the cables (winch also) and the earth on the body. I put it back together and it started first time. Been OK since.

Edited June 8, 2023 by V

[digger]

Hi UKTJ, sorry to hear you are having problems.

You might have good voltage but its the power ie amps in the battery that counts but assuming its ok.

Are you certain that all connections ie battery terminals clean and tight, starter terminals same etc that's where I'd start.

I had contact problems with that clutch switch on my last XJ. I don't know about the fuse, I just wired the switch out in the middle of nowhere and had no probs for the next 5 years!

I guess you know why I try to avoid deep water etc if possible.

Have you tried push/tow starting? If it does the you know its something to do with the starter system itself.

Edited June 8, 2023 by digger

[V]

There is another vulnerability to be aware of that affects at least TJs and post '97 XJs and that's the ignition switch actuator pin. It's a pathetic design and when the plastic pin snaps the engine won't start but some ignition switch functions still work. I have experienced it once before and it's a real head scratcher to find the cause if you are not aware of it's existence. I'm not saying you have this problem, just go through cleaning every contact face of every cable connection to your battery first. You only need one dull contact face in the wrong place to cause a no-start.

 

Sometimes when an actuator pin breaks just a little at the tip of the pin, there is enough slack in the key mechanism to start the engine by pushing the key deeper into the ignition switch while turning.

 

[UKTJ]

Thanks @digger and @V.  The US TJ forum I frequent has also pointed me at the ignition actuator.  I have been recommended what turns out as an excellent video where somebody is diagnosing a similar issue to mine, he identifies the actuator as the issue and then has a follow up video showing how to replace it.

 

I'm just waiting for Amazon to deliver a coiple of bits I lack toolwise to work through some of the checks shown in the video.

 

Thanks again for the help.

[UKTJ]

29 minutes ago, V said:

Terry, it's not unusual to experience battery terminal electrical contact problems following the type of terrain that you have driven your Jeep through recently. My Jeep refused to start a few days ago. Dead as a Dodo, but battery at 65% charged.

 

My engine bay was probably the same colour of Wales as yours. I jetwashed it as clean as I dared to, including the alternator windings. When it had dried out in the sun I dismantled every connection to the battery. Using emery cloth I made bright all of the electrical contact surfaces. The battery terminals, inside the clamps, on the nut faces of the clamps, both sides of every washer, both sides of every tube terminal on all of the cables (winch also) and the earth on the body. I put it back together and it started first time. Been OK since.

This has just reminded me, we forgot to measure my battery cables when we were in Wales.

[Caroline12]

7 hours ago, UKTJ said:

One odd thing may be that when I turn the ignition to try and start the Jeep the radio / clock turns off, but comes back on when the key is turned back

This is because, the voltage drops across the battery when you turn the key as the starter motor has power to it, amps is the important bit of starting, 

Your battery is flat, as soon as you switch off the voltage rises and restores power back to your clock/radio. 
 

several causes of this.

- mud/wet/tarnish connections as Vince said and vibration issues on connections when off roading. 

- alternator not charging the battery when running.

- age of the battery ?  and not run engine recently. 
- left side lights/power when not using it

check simple stuff first, eg: battery charges from a wall charger and keeps its charge. 

 

[digger]

A few more ideas to check if the simple ones don't work!  Always look for the simple things first.

Do your lights and wipers etc work, not if your battery is flat or bad connections.

Inspect all wires connections in starter circuits especially where exposed to damp etc(Vince)

Starter motor full of crud(oh dear may be a rebuild ,certainly a dismantle and clean,maybe replace), connections!, Bendix gear stuck in flywheel(try rocking car in gear to unstick)

Is solenoid round with a push button on the underneath. I f so pushing this actuates the solenoid manually in the event of a faulty one. If no button,  does  the solenoid  have bare terminals sticking out the top, I f so an old trick is to use a large insulated handle  screwdriver and short across briefly(you do not want to weld the tool to the job) , with care and insulation for hand. There will be sparks!!  If motor turns over then solenoid faulty!

Hot wire ignition switch to check if car starts in which case switch may be faulty!

Does engine turn? Try turning by crank bolt or rocking car in gear(higher gear is easiest)

[UKTJ]

47 minutes ago, Caroline12 said:

This is because, the voltage drops across the battery when you turn the key as the starter motor has power to it, amps is the important bit of starting, 

Your battery is flat, as soon as you switch off the voltage rises and restores power back to your clock/radio. 
 

several causes of this.

- mud/wet/tarnish connections as Vince said and vibration issues on connections when off roading. 

- alternator not charging the battery when running.

- age of the battery ?  and not run engine recently. 
- left side lights/power when not using it

check simple stuff first, eg: battery charges from a wall charger and keeps its charge. 

 

Battery almost new and used daily for last few months.

Started easily first time, no issue when son moved the car, absolutely dead 5 mins later.

[Cameron]

The first TJ I had came with an immobiliser if it didn’t recognise the key properly.  The guy I sold it to had a similar situation right after he bought it.  He disconnected it and the Jeep started.  No idea how he disconnected it though.

[UKTJ]

35 minutes ago, Cameron said:

The first TJ I had came with an immobiliser if it didn’t recognise the key properly.  The guy I sold it to had a similar situation right after he bought it.  He disconnected it and the Jeep started.  No idea how he disconnected it though.

Was that a '97?  As I understand it that early system has caused a lot of issues.

[Cameron]

It was…I had it for ten years with no issues and then as soon as I sold it it occurred.

9 hours ago, UKTJ said:

Was that a '97?  As I understand it that early system has caused a lot of issues.

 

[UKTJ]

OK, so my new multimeter leads with clops on arrived and I carried out a check on the ignition circuit.  Turning the key delivers just under 12v to the post on the starter motor connected to the ignition.  So not a broken actuator pin.  I presume this means it is likely that the new starter motor I recently fitted is dead.  Does that sound right?

 

I could get grumpy, but if that is the case I guess water exposure may have been the issue.

[Caroline12]

Does the starter turn the engine at all now ? 
check with a insulated handle screwdriver as Phil said above. Jump power from main +12v to solenoid connection, to see if it fires in and turns the engine.

 

21 hours ago, digger said:

If no button,  does  the solenoid  have bare terminals sticking out the top, I f so an old trick is to use a large insulated handle  screwdriver and short across briefly(you do not want to weld the tool to the job) , with care and insulation for hand. There will be sparks!!  If motor turns over then solenoid faulty!

 

It gives you a jump the first few times I did it, now I know what happens and I’m used to it. But my big screwdriver has burns/melted metal on it from testing the solenoid on starters. 

Do NOT use copper cable to do this test, the copper melts and then welds itself to the starter posts. Use a single piece solid steel metal bar with a good insulated handle to do this test. 
 

sometimes, they just fail for no reason, mud and water do destroy them quicker

[Caroline12]

1 hour ago, UKTJ said:

OK, so my new multimeter leads with clops on arrived and I carried out a check on the ignition circuit.  Turning the key delivers just under 12v to the post on the starter motor connected to the ignition.  So not a broken actuator pin.  I presume this means it is likely that the new starter motor I recently fitted is dead.  Does that sound right?

 

I could get grumpy, but if that is the case I guess water exposure may have been the issue.

Water exposure, is probably the answer, you can get them refurbished. You could always keep a good spare ready for emergency. Change it, get the old one overhauled this is what we recommend to customers with CHP gas generator engines. 

[Caroline12]

20 hours ago, UKTJ said:

Battery almost new and used daily for last few months.

Started easily first time, no issue when son moved the car, absolutely dead 5 mins later.

This does not mean the battery is charged, it maybe 12V on multimeter, but unless you check the battery amperage you won’t know.
If you don’t have a battery tester, put it on charge and see how long it takes to fully charge. If quick, it was charged, if not - then flat. 

don’t use your multimeter to test battery amperage, it will blow the multimeter fuse or blow it up. 

[digger]

56 minutes ago, Caroline12 said:

Water exposure, is probably the answer, you can get them refurbished. You could always keep a good spare ready for emergency. Change it, get the old one overhauled this is what we recommend to customers with CHP gas generator engines. 

I presume you have dismantled/cleaned etc the cable connections etc at starter.

I f so I'd dismantle the starter and if full of crud you might try cleaning thoroughly. Sometimes the mud etc has just clogged up the whole thing and the brushes are jammed solid and won't operate.  You should clean the gaps on the commutator but do this carefully because this is where the insulation between the copper bars is and you do not want to destroy it, just clean and scrape out any carbon from brush wear. To reasemble it can be a fiddle to get the commutator back into the brushes. Just wedge the brushes open with the springs,  fit comm , then push  brushes back onto comms and it will sort itself out! If still no go get it reconditioned as Caroline suggests, its much cheaper and has always been good for me. You probably have a local reconditioner ours is a same day service1

[digger]

1 hour ago, Caroline12 said:

Does the starter turn the engine at all now ? 
check with a insulated handle screwdriver as Phil said above. Jump power from main +12v to solenoid connection, to see if it fires in and turns the engine.

 

 

It gives you a jump the first few times I did it, now I know what happens and I’m used to it. But my big screwdriver has burns/melted metal on it from testing the solenoid on starters. 

Do NOT use copper cable to do this test, the copper melts and then welds itself to the starter posts. Use a single piece solid steel metal bar with a good insulated handle to do this test. 
 

sometimes, they just fail for no reason, mud and water do destroy them quicker

Hi Caroline,  so you've learnt the hard way re shorting the terminals with  wire too.   The one time I tried it was in a field about 50 yrs ago and I was desperate. Mk1 Landy was no go! I borrowed a thick (so I thought!) piece of wire from the farmer's fence!! It blew , like a no earth fuse!! .  LOL .

[Caroline12]

Yes, I learnt the hard way

[digger]

Hi UKTJ, I forgot! Don't go mad greasing the bearings. You do not want it in the brushes. If phosphor bronze bush then this should be cleaned and soaked in oil then wiped off.

[V]

Two in-the-field tricks that sometimes work with a dodgy starter motor are:

1. Banging the starter motor with something steel while an assistant turns the ignition key. You don't want to dent or crack the starter motor just provide a little shock and vibration to disturb the solenoid.
2. Removing the starter motor from the bell housing but keeping it wired up. Clip a negative jump lead to the starter motor housing and the other end to the engine. Then try the starter motor on the ground a few times turning the ignition key without the flywheel load. If it makes a noise and whirs, reinstall it and try again.