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Battery is good and charged.
Red key is in ignition and the instrument cluster lights up when turned.
Car won't crank.
-When Pin-14 is wired to jump post, the starter runs.
-Corresponding pin-14 connector on chassis side does not light up 12V check bulb
-Fuel pump jumped and it runs
Before I buy a brand new ignition switch, I want to make sure if this is the frist thing I should replace.
Ahh OK I get it you have a jumper instead of a relay at location XV
then try another starter switch.
Any chance you can post a picture of your CE panel?
Try pressing the rear of the connector into the into the rear of the switch that might show a loose connection then turn the key and see if it cranks while holding the harness connector into the switch
Stan: I will take a pic of the CE panel. The manual jumper feels pretty secured in the slots. I will take a pic on Monday when it stops raining cats and dogs.
Dr. Bob: I will check the voltage. Even is the battery is weak, it should at least crank right? It cranks when I jumper the pin #14 with the jump post, so the connect for the ignition system beyond this point (starter, harness, etc) should be good right? What happens if the voltage is good? If it is bad, does it mean the switch is likely bad?
Hoi, the circuit goes as follows:
yellow wire - from starter switch terminal 50 to plug position A6 on the CE panel
black wire/ part of CE panel - A6 terminal 30 at the "bridge" relay socket (j60)
metal Bridge to terminal 87 on relay socket
black wire/ part of ce panel - terminal 87 to plug position O5 on the CE panel
yellow wire - from O5 to 14 pin connector
No less than six 38 year old connections from switch to starter. Im surprised any of these cars start.
Check for battery voltage at that jumper with key in start position. That's the midpoint between the switch and the 14-pin.
Voltage at the jump post is same as at the battery.
Here is a picture of the CE panel. In decent shape considering the overall shape of the car. The metal jumper at XV is nice and tight without any signs of loose connection or corrosion. I will update and replace the fuses, since the passenger side lights are not working and some fuses are already incorrect as I just glance at the top row.
Voltage at the jump post is same as at the battery.
Here is a picture of the CE panel. In decent shape considering the overall shape of the car. The metal jumper at XV is nice and tight without any signs of loose connection or corrosion. I will update and replace the fuses, since the passenger side lights are not working and some fuses are already incorrect as I just glance at the top row.
What is that black jumper cable in Z slot?
Not jump post in engine compartment, metal jumper in relay socket xv. It is indeed about halfway between the starter switch and the starter.
If you're going to be buying these things left and right you should strive to master the electrics: ... you'll need this skill often.
Take the time to learn how to read the diagrams...they look like greek at first but they're actually the best diagram design I've ever seen for any car. Once you have the diagram logic down, and familiarize yourself with the component locations (many on which are on CE board)..the wiring logic in early 928s is VERY simple. The early diagrams were published in color and those make it all that much easier.
Key to diagrams:
Knowing the fuse numbers and relay locations/ numbers is half the battle, but also familiarize yourself with wire positions in the CE panel plugs along the bottom:
1 8
2 7
3 6
4 5
These positions are numbered at each of the plugs on the board.(very small numbers) With few exceptions, almost every circuit in the car passes through these plugs, and they're often a problem.
If you can, check the voltage at terminal 50 on the starter switch with the key in the start position...this can be a small pain to access, so if you can't you can do a lot of testing in the CE panel.
with key in START position check voltage in this order on CE panel:
Plug A position 6. big fat yellow wire...(I see it in your picture) comes from key and should be +12 with key in start position. this wire comes from ignition switch. If no juice there, problem is at switch or in switch, or mice ate that wire somewhere along the way. Pull the plug, spray the connectors, etc.
If juice is at A6, move on to terminal 30 in relay xv. This is the next stop on the long and high resistance journey to the starter, and the location of the jumper bar dr. bob referred to. If no juice here, there's a break in a black wire on the back side of the relay board. if juice here then move on to..
Plug O position 5.. another big fat yellow wire, I see that in your pictures too. If no juice here, there's a break in a different black wire on the back of the board. if juice here, the next stop is the 14 pin connector at the jump post in the engine bay.
A few things to remember...its a logic flow, if you check it in order that the circuit is designed, you'll find the problem. If you bounce around randomly trouble shooting can get pretty confusing.
Important..there is a high likelihood that you have a bad connection at one of these locations..as you're testing and poking around with the key in the START position you my find said bad connection and poke it just enough to fix it, so be ready for the car to START at any time (you know..neutral, parking brake, etc)
The CE panel is just a bunch of wire connections..no foil board or circuit board in there. here's the back:
There's rarely issues back here but I have seen melted/burnt wires occasionally.
It's a good idea to service all the fuses, but there's no fuse in the circuit you are having issues with now.
Just pulled the CE on my 82, as it won't stay running. I can see it has definitely been off before, and my black jumper is not on the same terminals as hoi's. I know it is a few years newer, but weird that it's not in the same spot, to me anyway.
05-12-2017, 05:19 PM
'79 Manual: Ignition Switch Problem?
you should strive to master the electrics:
... you'll need this skill often.
