Starter won't shut off even after new igntion switch

B

bavbob

Well-Known Member
Site Donor
Messages
3,610
Reaction score
1,759
Location
Boston, Ma
Turns out my ignition switch had not only had the crimps fail, the inner spring mechanism had fractured. Switch replaced and now FEELS normal................ but why would the ignition work appropriately and not give power to the starter with the key rotated to the "on" position, but once rotated to the start position and then allowed to spring back to the "on" position, continue to feed power to the stater?

Starter looks original so I assume wiring is correct but???
 
The ignition switch typically sends power to a relay or solenoid that in turns connects the battery to the starter. The relay or solenoid can stick causing the starter to keep going. Check the wire going to the relay to see if it is still sending current when not in the start position.
 
Electrical diagram shows no relay for the starter as I too thought this was the issue. I just stared at the diagram again to confirm and noticed the stater has an internal switch that sends power to the coil, perhaps the switch is stuck so power from the coil keeps the switch activated. I'm gonna pull the power from the coil and see if the problem resolves.
 
Direct wire from 6:00 position on starter to wire you can touch to battery
If it still hangs it's the starter
 
No it does not hang. My ignition key inserts with the key in a vertical position, in my Bavaria it insets in a horizontal position. Wondering if it is the tumbler, ie, whole thing is rotated. Find that difficult to believe since ignition switch fits in only one way and it engaged the tumbler/key the way it should. Just graspin. Starter has to be replaced anyway at some point.
 
Sounds like the solenoid is stuck, or it is hanging up because the bendix (return spring) mechanism is probably gummed up, as mine was. All this stuff is easy to take apart and clean, if you are so inclined. Good to do with a few Spaten Optimators....
 
Pull the black wire from 6:00 and use a voltmeter to see if 12 volts is present after you release the key
 
bavbob said:
Starter has to be replaced anyway at some point.
Click to expand...

The problem is that a few instances of letting the starter run after the engine has started can chew up the ring gear. So you can replace the starter, but the real damage will be elsewhere. In extreme cases, that chewed-up RG will then damage the pinion gear on your new starter.

In other words, this condition needs to be addressed.

sfdon said:
Pull the black wire from 6:00 and use a voltmeter to see if 12 volts is present after you release the key
Click to expand...

Yea, that would be a good diagnostic to sort out whether it is the ignition switch, solenoid or coil wiring.
 
To answer your specific question, I read somewhere that a wiring problem in the load shedding relay can cause a continuous feed of power to the starter. Pull the load shedding relay and see if your car starts normally or still has the problem you describe.

Having said that, it is more likely that the starter is your problem as Don noted.
 
12V to black wire with key turned so that oil etc light is on so the question is why. Load shedding relay is where on a 73 euro? I read a post said its below the fuse box, I have nothing there other than 2 relays, the one for the turn signals and a black one. I disconnected both and still have the issue...grrrrrrrrrrr
 
I agree, I will end up removing the entire cylinder. The black wire goes straight from the ignition switch to the starter and is hot when the key is turned so its the problem. Any chance wiring to the starter is wrong? Pos from battery to right connection, black wire to the left spade so I got two hot lines to the starter.
 
bavbob said:
The black wire goes straight from the ignition switch to the starter and is hot when the key is turned so its the problem.
Click to expand...

When you say "when the key is turned" do you mean "turned to 'on' " or "turned to 'start' " ? If the black wire goes hot whenever the switch is "on", then yea, that's the problem. As Chris said, "circle back to the switch even though you replaced it"

Any chance wiring to the starter is wrong? Pos from battery to right connection, black wire to the left spade so I got two hot lines to the starter.
Click to expand...

No, it sounds like your started is wired correctly. The problem is that you "got two hot lines to the starter" when you should have one hot always (from the battery) and the second wire hot only when the key is in the "start" position.
 
You are looking in the wrong place for the load shedding relay. I have seen the series of posts where someone on the forum thought that the A/C relay installed below and in front of the fuse block was the load shedding relay. If you continue to read through that post you will find that they later discover they were looking at the wrong relay.

My load shedding relay is above the hood latch handle on a bracket mounted to inside of the left front fender. It is the relay of the two mounted further forward.
 
I found three, 4 pronged relays near the fuses which when all were pulled, still had the issue. Gonna swap em all out anyway since they are original.

On my Bavaria, there is a relay attached to the brake booster near the firewall, a PIA to get to but when my Bav was dead, I ended up finding one wire spade loose to that relay. There is a similar one on the 3.0.

Yes, when the key is on as well as when the key is in the start position, starter kicks in.

I wired my ignition switch like the old one, but this does not match the wiring diagram I have which is for the 74 cs not 73. Prospero's garage has no diagrams for a 73 euro cs, only US versions.

I will loop back to the ignition if the load relay gives no answers.

Appreciate all input up to this point and in the future.
 
I am not sure I would replace the relays just because they are old. They rarely fail, and usually only cause problems when the connections oxidize, which can easily be repaired. Secondly, some of the relays in our cars are wired in a way other than what has become the standard relay layout. Thus, a newer relay may fit into the socket, but the relay terminals may not correspond to the wiring in the socket. This pattern has been standardized and is not a problem in later years, but with our cars it can be a problem.

To summarize my understanding, a problem in the ignition switch and/or a problem with the load shedding relay are the possible causes of your trouble. Look at the relays above the hood latch.
 
bavbob said:
when the key is on as well as when the key is in the start position, starter kicks in.
Click to expand...

OK, that's the source of the problem. Something about the ignition switch, or the way the wires are connected to it, is wrong.

I don't see how a defective load-shedding relay could cause a starter to run on. The LS relay is a pretty simple, SPST device. When it fails, it typically just doesn't switch to ON when the switch is turned to "run". But even if it stuck in the ON position, it wouldn't cause your starter to keep running.
 
Jay -- I had the same load shedding relay problem you had -- faulty voltage regulator caused the alternator to put out too much voltage and fried my load shedding relay. Back when this happened, I read everything I could find on this, including your thread. I keep bringing up the relay as a possible source for the problem because I read on this forum that a forum member had observed this "starter continues to run" problem in connection with a problem he had with his relay. Given the way SPST relays work this doesn't make a lot of sense to me either, but on the off chance this might actually fix bavbob's problem, I will continue to bring it up until bavbob eliminates this as the source of his troubles
 
Some thoughts-disconnect the black/red wire at 12:00 on the starter
Test for 12 volts now on the black wire @ 6:00 with key on
A bad diode at the alternator will feedback through the blue wire into the green wire into the black/red wire.
It will keep your starter engaged
 
Thank You, I will keep you posted after I perform this.

I cleaned all spades on bank of relays near the fuses and this had no effect. I also checked the relay designations and they matched a new set I had so I swapped those out temporarily, still no effect.

There is a relay near the coolant reservoir that the black/green striped wire too the starter emerges from. Relay is functional as I hear a click when hooked to 12v source and when engaged, no power to the stater. I cannot get this relay to engage with the key in either "on" position, ie no click. This fit any scenario?
s-l1600.jpg

relay
 
You must log in or register to reply here.
Back
Top