69 Road Runner completely dead , help me diagnose problem.

[1Bad70Charger]

My 1969 Road Runner with its new 505 ci engine and reverse manual transmission (727) has been very reliable since getting built this winter, and I have driven it 700 miles to numerous cruise nights without any issues at all.  Car has new battery and rebuilt alternator also.  I have noticed the car has been taking a charge just fine when I drive it.

Well I jinxed myself tonight as I was telling a buddy of mine tha the car has been very reliable and never stranded me, but everytime I go to start it I realize that an old modded hot rod like this could just be totally dead and not start (and how its a bummer if that happens and you get stranded on the road or cruise night, etc.).

Well, left the cruise night tonight she fired up just fine, and driving home I realize that all gauges were lite up that come on when the headlights are on,but the headlights stopped working on the way home (but interior gauges and tach still were lite up).

Car got me home no problem and went out to trouble shoot it to see if my tail lights were working 1 hour later, and when I opened the car door the dome lights came on and the ignition was working and then I shut off the ingition switch, and tried it again and everything went totally dead (talk about jinxing myself).  

NO dome lights, no cranking at all, no horn, 0, like having no battery in the car.  However, the only think that work is my toggle switch that runs my twin fans on my champion radiator and my vacum pump (for the big cam in my car) and these two features are wired direclty to the battery, so i know the new battery is still working fine.

I am not a mechanic, but seems like something is wrong with the ignition, as the car is otheriwise 100% dead.  I put the CHeetah shifte in all different gears to make sure its not the neutral safety switch but no help there. Also, checked battery terminal connections to make sure they were not loose and all was nice and tight.

Car has new MSD 6al ignition and MSD distributor also, and never had any issues all summer until now.

What are the most likely issues that are going on with my car based on what i describe? The fact that that everything is 100% dead, except my toggle switch wired direclty to battery for my radiator fans and external vacum booster which are both controlled by the same toggle switch (both kick on fine and have normal amout of power when turned on.)

Thanks in advance guys!  

[Rolling_Thunder]

sounds like your ammeter took a shit...       the give away would be the horn not working - that means there is a disconnect between the alt power lead and the batt power lead - those two connect through the ammeter --   disconnect the battery and crawl under the dash...    then connect the heavy red and black wires together and see if that does the trick...   

[1Bad70Charger]

sounds like your ammeter took a shit...       the give away would be the horn not working - that means there is a disconnect between the alt power lead and the batt power lead - those two connect through the ammeter --   disconnect the battery and crawl under the dash...    then connect the heavy red and black wires together and see if that does the trick...  

If its the ammeter does that kill the battery (like a bad alternator or no?).

Also, I take it there must be a direct relationship between the headlights both going out on the way home and then the car being totally dead 1 hour later?

Thanks for your input Rolling Thunder. 

[Rolling_Thunder]

honestly - what I have found with old cars is one electrical problem leads to others and things that seem related are several different problems.... 


Headlights going out = could be the headlight switch overheating

The thing is when you said it had dash lights and dome lights then you keyed the ign off and back on - it had nothing...      that is the weird part. 

The dome light, ign, and other things are on different fuses...   so i doubt all the fuses blew at once (check anyway) --  All the items that do not work are all however, connected to the ammeter. The power comes in off the batt on the heavy gauge wire on the "J" terminal on the fuse block. If there was a disruption there the entire car would die. That would mean the ammeter OR the fusible link. The fusible link is easier to check -  look at it and see if the insulation has melted off  -- 

The power goes in on the red wire, through the bulkhead, to the ammeter, and then to the rest of the car...    so any problem with the ammeter OR fusible link would cause this condition.     

If your accessories (fans & vac pump) are hooked directly to the battery they will still work in this situation.    I have also seen the "J" red wire fy on the passenger side of the bulkhead connector...   just look around and note anything out of sorts.

Were these new harnesses or older ones ? 

[b5blue]

Check the bulkhead connectors, main ignition connector to the switch. Check and wiggle all fuses and connectors behind the fuse block. 

[Just 6T9 CHGR]

main ignition connector to the switch.

This one left me baffled...could have sworn it was a battery but it turned out to be the previous owners hack job using butt connectors & spade terminals to connect to the ignition switch....check that connector!!

[1Bad70Charger]

Thanks for the info guys I appreciate it. 

Any other opinions please keep them coming.

When its resolved will let you guys know what it was.

[Chryco Psycho]

start testing where you do still have power , the start relay is first , check the fusable link off that then in to the main bulkhead connecters , then the ign switch plug & ammeter . work through the path logically & see where you lose power

[1Bad70Charger]

start testing where you do still have power , the start relay is first , check the fusable link off that then in to the main bulkhead connecters , then the ign switch plug & ammeter . work through the path logically & see where you lose power

That makes alot of sense.  

Could be that my new battery is drained of most of its power b/c of something not working properly in my charging system, given the fact that my headlights went out on the way home.

Its actually taking a charge right now with my battery tender battery charger, and we shall see if the battery is drained, but has just enough power to power the toggle switch to my 2 elec. radiator fans.

If the battery has 0 to minimal juice have to get that charged anyways so will see how dead the battery really is and then of course have to figure out what caused it go dead (alternator is rebuilt but not the first one that went bad).

[flyinlow]

Battery connections clean and tight?

[A383Wing]

Battery connections clean and tight?

yea..that's what I was gonna say....that should have been checked & tested first

[1Bad70Charger]

Battery connections clean and tight?

Yes, that was the first thing I checked last night.  

Unusual update, I have been charging my new (this year) heavy duty battery for 9 hours, with my Battery Tender Plus, battery charger, that puts out 1.25 amps, and the battery is still taking a charge and not fully charged yet (so that tells me that the battery had to me way low on power?)

However, despite the fact its been charging that long I reconnected the battery and still no power at all from no dome light, head lights, and of course no ignition.

I will contiue to charge the battery over night but don't forget the battery had enough juice to power my twin elec fans (at least 30 amps) and my external elec. vacum booster, so it still seems there has to be a bad connection as suggested in most the threads here.

Anyways, my engine builder and mechanic who built the car is swinging by in the next few days and hopefully he can trace down the problem pretty easily.

Does the battery being WAY down on power and still taking  a charge over 9 hours later, yet the car still being totally dead, exept for the aforementioned toggle switch, lead to any other ideas about what's going on.  

Thanks for your input gentleman.  

[flyinlow]

If you have a 80 amp hour battery that was dead it would take a 1.5 amp trickle charger over two days to fully charge the battery. Some batterys like the Optima take a special charger and technic if run fully flat.

Your radiator fans work now? No headlights,running lights,horn or starter now.Start with a test light ,ground the pigtail clamp to the engine or alternator. Start at the pos. battery terminal. Does it light? then work downstream, starter relay, firewall connector, ammeter,etc. until you find the break (open) in the circuit.

I made a Hillbilly (Michigan) test light out of an old sealed beam. It draws enough current to show junctions that have high resistance. The light will be bright on one side of the juction and dim on the other.   :

Check at the starter relay, near the brake booster, wires tight, is there power there? With the car in park you can jump across the the big to little terminal with a screwdriver. The starter should crank the engine.

A few ideas, good luck.

[1Bad70Charger]

Update, battery needed to be charged with a battery tender plus for about 15 hours and is know fully charged.

Unfortunately, car is still 100% dead except for toggle switch that acitivates the twin dual elec. fans and vacum pump. 

Mechanic coming over tommorrow hopefully who build the car.

Obviously, some type of bad connection or other problem that you guys reference, that caused the battery to get drained of power and now that battery is fully charged, is keeping the car stone cold dead, except for the aforementioned dual fans and vacum pump, turned on by toggle switch.

[68neverlate]

Hmmm... if you read through some of Nacho's threads on charging, you might get a better sense of what's happening.  I'd say your alternator gave up the ghost, causing the car systems to draw off the battery.  It sounds like you might have had a lot on at the time things went down, which means you would have been drawing a fair amount of current off the battery and through your ammeter.  My guess is the wiring somewhere between your battery to the ammeter or from the ammeter to the splice on the other side of the ammeter might have overheated and now needs to be replaced.  There's a design flaw in our cars (those having ammeters in them)... Nacho has a work-a-round to deal with this, but it takes your ammeter out of the picture (it won't display charging/discharging situations any more).  You may want to read through some of Nacho's threads for tips and situations to avoid (there's a fair number but here's one that gets into it a bit http://www.dodgecharger.com/forum/index.php/topic,33574.25.html) when mating up alternators and batteries (ie: low alternator output combined with high battery capacity is not good etc.)...

[BigBlockSam]

some thing happened to my roadrunner . everything was dead except the  switch for the aux electric fan . cause that was run direct from batt with an inline fuse .

it was the feed wire on the firewall bulkhead connector had fried .good luck 

[Brass]

As stated, it sounds like it could still be the bulkhead connector.  (If it was just headlights, I'd suggest checking your ground.)

Here is a very good article I located on this site before:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

Suggestion: an easy way to bypass the ammeter is to simply connect the red and black wires onto the same post at the back of the gauge.

You can also bypass the bulkhead connector by running the wire through the firewall grommet.  (Instead of drilling directly through as the article suggests.)

Good luck.

[Chryco Psycho]

You might want to install relays for the headlights & take the load off the bulkhead , ammeter & switches

[1Bad70Charger]

Great info guys on a topic very foreign to me.

Hoping for the best when my mechanic comes over tommorrow and thanks! 

[moparguy01]

Sounds like what my 68 coronet did to me. Mine ended up being the connector in the bulkhead where the fusible link plugged into it going bad.

[1Bad70Charger]

start testing where you do still have power , the start relay is first , check the fusable link off that then in to the main bulkhead connecters , then the ign switch plug & ammeter . work through the path logically & see where you lose power

Unfortunately it turns out that this is not going to be easy as its not the fusable link, bulkconnectors, and we found out by jigglig the wires behind the sun tach that the power (except for the headlights) returned, so my issue is right behind the instrument panel cluster and the dash board has to be removed to access those wires!  

Have a feeling the Ammeter took a dump which I am going to end up bypassing regardless of what we find and something burnt out with the headlights to (have at least 2 seperate problems we are going to find).

My engine builder was not use to removing the dash board on a 69 Plymouth or Dodge B-Body, and when I saw him struggling and found out he never removed one before, I decided to politely send him on his way, and I will have it flat bedded to a local old school Mopar Mechanic, who has a solid background with this type of electronics.

All the power from the engine bay area including the wire in from the alternator into the interior works, but the wire going out to the alternator from the dashboard area of the car has no power, explaining why the battery was WAY down on power and had to be recharged.

Any further thoughts are appreciated?  

[68neverlate]

The battery recharges when the alternator is putting out more power than the car is using and if the battery needs it.  If this is the case, the current flows from the alternator through the bulkhead to the ammeter and through that back out the bulkhead to the battery.  If any of that wiring is defective, the battery won't recharge. 

If there was a large draw through that wiring (as would be the case if your alternator stopped producing power and there was a large draw on your battery), the wires or ammeter could have got cooked.  Another possibility is that you developed a short in the headlight circuit somewhere which could also have cooked the wires near the ammeter.  If the headlight circuit still has the short, that might explain why power returned to everything else except headlights when you jiggled the wires behind the dash. 

BTW, in order to get the instrument panel out of the dash on a B-body, you have to drop the steering column...

Keep us posted... I'm interested to hear what the problem is.  Good luck. 

   

[dodgechar]

  My guess your bulkhead conectors . Thoughs clips are a flaw. That artical in madelectronic ts great. I'd recomend that amp by pass, but the bulkhead is probably the bulk of your troubles.  Also the ground from the neutral safety switch could  not be grounded all the way  If you had some tranny work it might be there too.

[1Bad70Charger]

The battery recharges when the alternator is putting out more power than the car is using and if the battery needs it.  If this is the case, the current flows from the alternator through the bulkhead to the ammeter and through that back out the bulkhead to the battery.  If any of that wiring is defective, the battery won't recharge.  

If there was a large draw through that wiring (as would be the case if your alternator stopped producing power and there was a large draw on your battery), the wires or ammeter could have got cooked.  Another possibility is that you developed a short in the headlight circuit somewhere which could also have cooked the wires near the ammeter.  If the headlight circuit still has the short, that might explain why power returned to everything else except headlights when you jiggled the wires behind the dash.  

BTW, in order to get the instrument panel out of the dash on a B-body, you have to drop the steering column...

Keep us posted... I'm interested to hear what the problem is.  Good luck.  

 

Sounds like a very possible scenerio.

You would agree to get to the wires behind the instrument panel out of the dash the dash pretty much has to come apart, or just the instrument panel by dropping the steering column.

How long of a job would you say it is with a competent mechanic to take off everything that needs to be removed to get to all those wires behind said instrument panel?

This really sucks, especially going into the last weekend of summer and the labor day holiday!!  

[Chryco Psycho]

It would depend on the competancy of the mechanic, I changed out a whole main harness in about 3 hrs including removing the dash , it would not take long to drop the column & pull the gauge panel but finding the issue coul dtake a bit if it is not obvious , it would only take a couple of minute to pull the wires off the ammeter , test it & jump the two wires together if that is the problem .