How to jump from engine compartment

Topic: How to jump from engine compartment (Read 1036 times) previous topic - next topic

How to jump from engine compartment

September 06, 2024, 08:59:58 pm

Hi All, I have a 2002 U295, Which I parked incredibly close to the fence and cannot reach the battery compartment and my battery batteries are dead (Long story, but been having charging problems.). I need to jump it from my engine compartment and I have a very good booster pack, which should be able to handle it. The question I have is how. Where do I connect the negative and positive? Here is a photo any help with the appreciated.

Re: How to jump from engine compartment

Reply #1 – September 06, 2024, 09:11:17 pm

Can you reach the starter? Closer is better. Picture you show is for the charging Isolator. Your starter will be on the drivers side

Coach wont start trouble shooting (Battery)

Re: How to jump from engine compartment

Reply #2 – September 06, 2024, 09:18:46 pm

I thought I was also looking at the boost, and starter solenoids. I thought it might be able to use one of them.

Re: How to jump from engine compartment

Reply #3 – September 06, 2024, 09:30:53 pm

Quote from: Safari360 – September 06, 2024, 09:18:46 pm

I thought I was also looking at the boost, and starter solenoids. I thought it might be able to use one of them.

Boost solenoid yes. Starter solenoid is on the starter. Cable crosses over to batteries with a union in the middle. Need to jump on the 4(O) starter cables. Is the generator dead?

Re: How to jump from engine compartment

Reply #4 – September 06, 2024, 10:12:42 pm

I am plugger into shore power. It is not charging. The fault code indicates something is wring with the batteries, and I am afraid it's the house set too. I am getting all new batteries. They have been a problem since I bought the coach a few months ago.

Re: How to jump from engine compartment

Reply #5 – September 06, 2024, 10:43:20 pm

You could jump off the boost switch but you would need an 8 D battery and if your batteries are
way down they may take too much juice to start. If your inverter charger doesn't work I would get
a charger and leave it on for at least twelve hours or longer with the boost switch on so you charge
both sets of batteries and then try starting it.

Re: How to jump from engine compartment

Reply #6 – September 07, 2024, 09:05:53 am

The starter isn't too far below your pic. As dsd asked, can you reach it?

A "dumb" charger could be hooked up at the boost solenoid and possibly revive the engine batteries enough to start it or at least assist the booster pack.

Re: How to jump from engine compartment

Reply #7 – September 07, 2024, 09:19:55 am

Quote from: Safari360 – September 06, 2024, 08:59:58 pm

Where do I connect the negative and positive?

Photo component ID. The blue finned device is your battery isolator. Directly to the right of isolator is the BOOST solenoid (silver cylinder). The two large black cables attached to the BOOST solenoid and going downward will eventually lead to your two battery banks. The cables may make stops at other components before they actually reach the batteries. I don't know which cable leads to the chassis (start) batteries. They (the black cables) have white ID labels. If you get the ID number off the cables and look at your 12V electrical schematic, it will tell you which cable goes to chassis batteries.

Attaching your booster pack to the (chassis) battery cable at the BOOST solenoid MIGHT work, but it is fighting all the resistance (cables, multiple connections, possibly bad battery) between that point and the actual starter. As Scott said, much better to jump right at the starter. Hooking up a battery charger at the BOOST solenoid, however, should work fine. Any good clean shiny metal on the engine should suffice for the negative ground point.

Schematic B-2126 linked below should be correct for OP's coach:

https://www.foreforums.com/index.php?media/file/b-2126-automotive-wiring-u270-295-320.3297/

Re: How to jump from engine compartment

Reply #8 – September 07, 2024, 09:43:03 am

Go for ground on engine. Cuts out all other connections.

On silver solenoid looks like right side goes to coach batteries. Based this on small wire (alternator?) connected on isolator.

Looking lower in picture below isolator there are 2 solenoids not sure what they are for.

Re: How to jump from engine compartment

Reply #9 – September 07, 2024, 10:05:21 am

Instead of trying to jump it, use the positive jumper cable to go to the boost solenoid you have in your photo. I just would connect to the right side as turbojack suggests and run your toad for at least 15 minutes at about 1000 rpm. You could use the boost solenoid switch on the dash also. To make sure, you could clean off the connection label on the top of the blue isolator and read it. If you can't get your head up there, use a cell phone to take a photo. And yes, use the engine as a ground point.

Pierce

Re: How to jump from engine compartment

Reply #10 – September 07, 2024, 07:25:38 pm

If you have the prosine inverter/charger it will not charge a dead battery. You can put a charger on the battery and you will have to do a reboot on the prosine.

Re: How to jump from engine compartment

Reply #11 – September 07, 2024, 09:26:36 pm

Quote from: Pierce & Gaylie Stewart – September 07, 2024, 10:05:21 am

Instead of trying to jump it, use the positive jumper cable to go to the boost solenoid you have in your photo. I just would connect to the right side as turbojack suggests and run your toad for at least 15 minutes at about 1000 rpm. You could use the boost solenoid switch on the dash also. To make sure, you could clean off the connection label on the top of the blue isolator and read it. If you can't get your head up there, use a cell phone to take a photo. And yes, use the engine as a ground point.

Pierce

I think what I'll do is try to put my smart battery charger on the boost solenoid, as you suggest, since it's the only place I can actually access the charging system, which is the original problem - Thanks to my parking choices.

Re: How to jump from engine compartment

Reply #12 – September 08, 2024, 08:46:36 am

Quote from: Safari360 – September 07, 2024, 09:26:36 pm

I think what I'll do is try to put my smart battery charger on the boost solenoid, as you suggest, since it's the only place I can actually access the charging system, which is the original problem - Thanks to my parking choices.

The smart charger may not work if the battery voltage is too low. If that is the case you will need a dumb charger to bring the voltage up. Then your smart charger can take over.

Re: How to jump from engine compartment

Reply #13 – September 08, 2024, 10:23:38 am

Dave,

Was your house battery bank also dead? You could just use the boost solenoid or even start the generator with it.

Nice to have solar so you don't have to worry.

Pierce

Re: How to jump from engine compartment

Reply #14 – September 08, 2024, 11:18:45 am

Quote from: dsd – September 06, 2024, 09:11:17 pm

Can you reach the starter? Closer is better. Picture you show is for the charging Isolator. Your starter will be on the drivers side

Coach wont start trouble shooting (Battery)

Is this the starter? If so, how would I use a booster pack to jump directly to the starter?

Re: How to jump from engine compartment

Reply #15 – September 08, 2024, 11:30:57 am

Red cable to the big lug at the top of your picture and any good ground with the black cable.

Re: How to jump from engine compartment

Reply #16 – September 08, 2024, 11:32:18 am

Quote from: Safari360 – September 08, 2024, 11:18:45 am

Is this the starter? If so, how would I use a booster pack to jump directly to the starter?

Crane man beat me to it.

If the battery is dead, this may not start the engine since the computer needs power also.

The more I think about it, I think you would be better putting charger on the batteries and at least get some charge on them.

Re: How to jump from engine compartment

Reply #17 – September 08, 2024, 11:36:18 am

That cable is not connected directly to the starter motor, it goes to the solenoid. It will back feed all the engine circuitry and you would have to use the rear start button or the ignition switch to start it. It could be used to charger the start batteries also.

Re: How to jump from engine compartment

Reply #18 – September 08, 2024, 11:47:56 am

The battery situation has one more factor, and that is that when I bought it, the chassis batteries would not start the engine without hitting the boost switch (and never since) so now that I'm thinking about it, I should be charging the house batteries. Could I put the dumb charger on the left side of that boost solenoid to charge the house batteries? I'm also wondering if I could attach the charger on the alternator feed to the Isolator (The middle connection on the blue box) and let house and chassis charge for a few days then use the booster pack if necessary.

Re: How to jump from engine compartment

Reply #19 – September 08, 2024, 12:10:30 pm

That would work also. If is easier to get to the starter cable use it and turn on the boost switch and all will charge.

Re: How to jump from engine compartment

Reply #20 – September 08, 2024, 04:40:53 pm

Use the left side of solenoid to charge your house batteries. If you use the center tap of isolator the batteries will not get fill voltage from charger. Between center tap and either side you will lose about .7 volts. The alternator is made to compensate for the voltage drop, your charger is not.

Re: How to jump from engine compartment

Reply #21 – September 08, 2024, 05:12:34 pm

Quote from: craneman – September 08, 2024, 12:10:30 pm

That would work also. If is easier to get to the starter cable use it and turn on the boost switch and all will charge.

This is what I'll do. I'm sure it will take a few days. Thank you so much. I'll let you know.

Re: How to jump from engine compartment

Reply #22 – September 08, 2024, 06:41:44 pm

Remember that the boost switch does not work for free. It uses juice staying energized (that's why it gets hot) so a trickle charger won't do the trick. Plugging the coach in will push a lot of amps into the house battery from the converter/charger and any loss from the boost switch will be minor. An hour plugged in should easily start the coach.

Pierce

Re: How to jump from engine compartment

Reply #23 – September 11, 2024, 11:18:57 pm

I was able to jump it with the booster pack after charging it with my dumb charger at 6 A (the max capacity of it) For a couple of days. I did as Suggested and connected the hot to the starter cable and grounded on the engine while leaving the boost switch on. The max voltage I was able to achieve was 12.4 with the boost switch on. The batteries do not seem to hold a charge, Even after running the engine for about an hour. I had 13.6 V while running and when I turned it off, it was at 12.2. It's obvious, I think, I need to replace my house and chassis batteries, I've known that for a while, but they have gotten worse and the orosine 2.5 seems to tap out every time I try to charge them on shore Power. Not positive how to reset it, But chat GPT made a few suggestions that I don't completely trust.

I really want to buy lithium house batteries, but I am not sure that the prosine 2.5 can handle them, but I have read that it can if you make a few adjustments to the charging regime with the pins, which I don't know how to do, but I could figure it out.

Anyway, thanks for the help. I really really appreciate it.

P.S. I know there is ample information on this forum relating to this question about my current prosine 2.5 and a gradual transition to a operable lithium system. If anyone knows of a thread that contains solid information about this specific question I would certainly be grateful for a link.

Re: How to jump from engine compartment

Reply #24 – September 11, 2024, 11:52:40 pm

Remember that the booster swich is designed to join the batteries to start in cold weather or if one bank is down, to enable charging both banks at the same time. It does draw current if left on and will result in lower battery voltage and eventual depletion.

Pierce.

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