Hi all.
You won't believe this one. I finally had some time today to address that pesky rear abs light that has been staying on for the last year. I disconnected the batteries, removed the lower 2 dash finish panels, removed the instrument panel surround and pulled out the offending bulb. Re-assembled every thing, hooked up the batteries.........No start. BTW this is an 87 6.9 with an ATS turbo. I re-checked everything at least 3 times. Can't figure it out. I did notice that the wait to start light stayed on longer than normal, and when I turned the key to the start position the light in the radio dimmed, so something is obviously drawing amperage.The glow plugs are new, and the controller is also. Any help would be greatly appreciated.

Thanks
Peter A.

 

you sure the trans in in park (if automatic)

 

It seems logical that LOW batteries could cause the glow plugs to take a longer time to heat up and longer for the WTS light to go out.

Of course it's drawing current, you are energizing the glow plugs and then the starter as well as the radio and whatever else is turned on. I think that what you mean is that you believe it is drawing excessive current through a short circuit.

What I suspect here first, is simply LOW battery charge. Otherwise I would expect a blown fuse, fuse link or the odor of burning wires if something was shorted. Since the WTS light is coming on (longer than the normal 10-12 seconds) that might indicate a low battery charge and "START" position is drawing down the voltage as evidenced by the radio light going dim. With low voltage from the batteries it will do that. The starting system/glow plug wiring and fuse links are probably OK. (but see last question below)

By the way, the voltage gauge should show a significant drop as the glow plugs draw current during the first 10-15 seconds (if its cold out) and continue to show a drop during the afterglow cycle that can go on for up to 2 minutes in cold outside temperatures. When the after glow cycle is complete the voltage gauge will come the rest of the way, back up to normal voltage reading.

I THINK that the gauge should also indicate a lower voltage (needle drop) as current is applied to the starter if the gauge is in fact connected and functional when the key is in the START position. I've never watched it for that but it might be similar to what you saw with the Radio light.

It's a slow moving/slow responding gauge. However, if there is a big problem in the starting circuit like a short in the starter solenoid/starter it should be very evident on the gauge. (a big and fast voltage drop).

That is what I THINK would happen.


1) Seems like something drained down the batteries or they are getting old and not holding a full charge.

2) It could be the solenoid on the starter going bad or like "stuck." A common remedy SOMETIMES is to bang on the top or end of solenoid with something. It's a tight fit under there so I don't know how you would do that - I've never had to do that on my truck starter. I would avoid hitting it near the cable connections.

If it does the same thing with fully charged batteries I would suspect the starter.
In the absence of finding any other cause I would pull the starter and test it.


So, this is just a partially educated opinion, I went through electrician's school 35 years ago so I understand the principles and the science but not well versed in practical automotive electric.

As a side note: I ALWAYS turn everything off when I shut down a vehicle and remove the key: blower motor, RADIO, wipers etc. All turned OFF and there are good reasons for that. I won't have any extra electrical loads as I start the vehicle (and these trucks tend to need all of the starting current they can get). Secondly if there is something amiss with wiring it's less likely to drain down the batteries when the components are turned off when the vehicle is not running.

After market radio/audio system wiring seems to be a common problem area that I have encountered with vehicles that won't start or have dead batteries. I seem to recall one vehicle that blew main ignition fuses that took weeks to fail (along with some other electrical problems) but was due to stereo system wiring done by those professional 'car stereo' guys.

'Do It Yourself' wiring can sometimes be a mess and cause a few problems if not done exactly right.

OK Back on topic:

With the symptoms you described I can only think of 1) and 2) above that I perceived as likely causes.

I hope that helps a little bit. It seems more like a problem in the high current carrying circuits and components (cables/big wires/starter solenoid/starter) rather than low voltage LOW current wires (small wires) like behind the instrument panel and under the dash.

Did you charge up the batteries to full charge and try it? What happened? Has the starter solenoid on the starter ever engaged and turned over the starter?

What have you tried so far?

6:30 AM and I've been up all night so, very tired brain fogged and writing too much - not even capable of looking at schematics right now although I DO have them for your truck and I'll try to help you solve the problem if you haven't got it figured out already.

I'd like to hear if anyone else has an opinion about what it might be. Others here have much more experience with automotive wiring than I do.

By the way, how long ago did you replace the glow plugs and controller? If it was close to the time this recent problem occurred it could be related.

PS: I SEE from another topic that you started (linked below) entitled 'no start' that you replaced the glow plug controller in October 2016 which solved THAT problem and the Glow Plugs at some later date. The controller apparently has been working fine since then and this current problem is unlikely to be related to the controller or the glow plugs. If you didn't install Motorcraft (made by BERU) type 'ZD9' (for your truck) glow plugs , be sure to buy those next time.

https://www.ford-trucks.com/forums/1...l#post16761604

 

36 degrees right now. Too cold to do any thing other than hook up the battery charger and wait for warmer dryer times. After going over your reply, I agree with the battery or starter diagnosis. As soon as the monsoon slows down, I will go out and check battery voltage and a few other things on your list. [ the 2 fusible links ] etc. Thanks for the extensive reply. Lot's of good info. I will keep you posted.
Peter

 

Just so you know, the key going to the start position actually turns off a few electrical loads like the blower, radio etc.

Simple test - put the truck in neutral, pop the hood, grab a screwdriver and go to the passenger side fender well starter solenoid/relay.

Put your screwdriver across the two large terminals, and you should see a couple little sparks and it should crank.

If you just hear a click, it's time to take a good look at your starter.


P.S. 36 degrees? Wow, that's warm. Try having starting issues due to a /frozen/ starter at 10F. That's fun!

 

As you get older you forget little shortcut diagnosis tricks like that. Truck fired up right away.
I quess I'll be looking at the wiring from the starter solenoid back to the ignition switch. I must have disturbed something while removing the ABS warning lightbulb.I will keep all of you updated with final outcome.

Peter A.

 

I am looking at this problem in a different way, after finding out that I can jump the fender mounted starter relay to start the truck. I don't have a glow plug, or control unit problem. I seem to have a starter circuit problem. Today I checked all of the fusible links by the relay area. All fine ! Next I checked and replaced the column mounted ignition switch. I then checked the wiring to the starter motor....
All ok. The column mounted switch is being actuated by the rod to the key switch
but, the column mounted switch is not actuating the fender mounted relay. I really don't know where to look at this point. I'm thinking of simply wiring a remote start button to the relay, but not knowing where the actual problem is, will bug the crap out of me. Any ideas ?

Peter

 

Check the clutch safety switch.

 

It's a C-6 automatic, but I did check and adjust the neutral safety switch as per the manual. I'm at a loss !!!

Peter

 

I'll show you all of the wires (which wire colors from the ignition switch) to follow, splices/connectors to check and post a couple of schematics. I looked at them earlier today anticipating you might need it. I was too busy to sort it out and post it then.

I'll get to that in about an hour or two. Too late to work on your truck at this time of night anyway (I presume).

Also, I have the same year truck, wiring should be identical and I can go out and look and maybe take a picture of something if needed.

Going through ALL of the related schematics to find the location of every splice, connector and ground is very time consuming as the information is not all in one place in the over 3,000 pages in 5 manuals. Fortunately I have done most of the work before and have copies of those pages in special quick access folders.

So I'll put the most important stuff up first- and ACTUALLY that should do it.

If not we can dig into it some more.

 

I know which wire that is, what it splices into and where it goes.

Plus a couple of other wires to check.

I am just sitting here waiting for some morphine pills to work so I can start to do this.

 

Yeah, Haha. MacRobb saved the day on that part of it. Ruled out the starter, cables going to it and battery charge. I've done that at least a hundred times, who'da thunk? ?

In my case I was sort of brain dead tired - from insomnia that night and brain fogged by morphine that I have to take 3 times a day (or I would hardly be able to get up out of my chair). Pain from shoulders to feet 24/7 so I have to take those pills or I won't be able to do anything. Also impairs my concentration in a big way so I can lose track of what I am writing about after 3 sentences. (Like right now)

That part of the wiring is pretty simple. Should be EASY. I can get on this in probably 1/2 hour.
No inconvenience at all I enjoy helping people and I enjoy the challenge of solving or helping to solve problems. It's a struggle with the side effects of the pills and the chronic pain issues but focusing on problem solving keeps my mind working so I don't lose it.

You know, "Use it or lose it" scenario. My mind is doing this 'problem solving' thing almost all the time anyway, it's a deeply engrained habit for many decades.

It's me vs. the pain and then the side effects of the morphine - every day and night.
At least it relieves the pain enough so I can do things and I'm not complaining! Just typing unnecessarily as my mind wanders.

I'm fine, really! Happy I have this much. it could be worse!

 

Chronic pain is something that we all arrive at sooner or later. I also have my demons. I'm glad to see that you have found some of the answers to fighting pain. Keeping your mind busy and your attitude positive !
I really appreciate all of the help
Peter A.

 

Haha. This is another one of those "Duh" moments. After going through all of this I figured out that its a 99% chance that the start relay on the fender well has failed.

Here is how I came to that conclusion while I had written the following.

OK, here is the easiest place to start. I hope these images are clear enough. I converted them and reduced the file sizes in an image manipulation program a long time ago before I found a better method that makes the clearer. If any image is not clear enough or if you have any questions, let me know. I can redo the images and help with any questions.

BASIC IGNITION CIRCUIT:



The upper blue rectangle represents the ignition switch that you just replaced. Lower right shows an R/LB wire (Red wire/Light Blue 'stripe' or aka 'tracer'). That wire is energized when the key is turned to "Start" and it closes the circuit (allows electricity to flow) to the Starter Relay on the Passenger side fender well shown in the next diagram - (Look for the M inside the Blue Triangle)
That marks your Red/LightBlue stripe wire:



C177 is a wire Connector. I didn't look up it's location but It should be very close to the Starter Relay. It might be the one on the end of the wire. On my truck the Red/Blue-stripe wire is SMALL, it has a 90 degree connector on the end that slips over the SMALL threaded post on the relay, which on my relay is on the TOP, (It's an after market relay - I've seen those posts on the bottom and others with two small posts top and bottom) I am going to GUESS that it is labelled "I" for 'ignition'. It does NOT go to the large threaded studs on the relay.
Check that it is making good contact on the post..

It appears in the schematic that THIS wire provides the low voltage current through the electromagnet coil that CLOSES the contacts in the relay that allow the High Current to the starter solenoid through the 8 gauge RED wire. That solenoid causes larger contacts to close that allow full battery power (voltage x current draw) to the starter windings through the 00 gauge cable from the batteries.

This all appears to be as simple as your relay finally got too corroded inside or the small wires in the coil burned out. A small hammer tap-tap might be a temporary fix but I would just replace it.

By jumping across the two large threaded studs on that relay to start it you are bypassing the low voltage side of the relay the small coil that normally closes the contacts. That's the part that has probably failed.

That being said, there is a whole bunch of other stuff in this "Start" position circuitry that I did not show. Hopefully, a failed relay is the simplicity of it.

See? Electrical isn't very difficult. When I saw that the wire went to the coil inside the relay, I thought "Duh!" It was a no-brainer that we should have thought of in the first place. Like Macrobb did about testing the starter.

Well, at least you have a new bulb and a new ignition switch and probably a good used spare ignition switch... and I HOPE not an old ABS bulb that is actually still good.

Check to see if that wire is making a good connection before replacing the relay and if you have a test light (voltage tester type with no battery inside of it) or volt meter TEST THE END OF THAT WIRE when the key is turned to start. If it lights up then it pretty much has to be the relay.

 

I forgot to mention yesterday that I did in fact replace the fender mounted relay after Macrobb posted the suggestion about the screwdriver starting method. This morning I pulled the angle connector off of C177 at the relay, and hooked up a test light. No Go.

Peter