switch issues (update Brianmoore

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m_jermyn
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Post Tue Jan 16, 2018 7:18 am

Looking for help.
84 E30 318i 3 speed auto. ZF 3HP22 (i believe)
Inhibitor switch playing up and having issues starting on hot days unless i wiggle the shifter.. Its getting worse and will leave me standard I'm sure..

How can I bypass this switch?

I have found a diagram for bypassing it when converting to a manual tranny but at this stage I'm leaving it auto.

I have found a little single wire under the dash that is

black/yellow (plug) Green/black

Now if i unplug this the car won't start
there is a relay right under the glovebox and off this relay is a
Green/back wire and a matching plug as above but only one side.

Now if I unplug the Green/black wire and plug it into the stray green/black wire I'm told it will bypass it.. But it hasn't worked..

Any help greatly appreciated
Last edited by m_jermyn on Tue Feb 06, 2018 11:12 am, edited 1 time in total.
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Satan
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Post Tue Jan 16, 2018 9:28 am

I had this issue a few years back and resolved it by joining a couple of cables together behind the glovebox but I can't remember which ones as it was Pacer that told me how to do it.

Someone should be along soon to help you out.
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Brianmoooore
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Post Tue Jan 16, 2018 1:58 pm

First of all, does your gear selector lever line up properly with the markings on the illuminated scale? If not, the root of your problem is likely to be with the engine and gearbox mounts, allowing the whole engine and transmission assembly to have moved out of position slightly.
There are two single pole plugs and sockets hanging out of the wiring loom along the top of the area behind the glovebox. Each have a black/yellow wire going to one side and a plain black (probably) wire going to the other side.
Pull both of these plugs and sockets apart, discard the halves that have black wires, and plug the two black/yellows together. This will convert the starter circuit to that used on a manual E30.
Disclaimer: I strongly recommend you do not do the above, of course, since there is a strong possibility that at some point the car will be started in drive or reverse, and an accident may occur.
m_jermyn
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Post Wed Jan 17, 2018 9:59 am

Brian,

That fixed it.. cheers for your advice as always..

Don’t plan on keeping it auto as I have a S14 I’m building for it.. Auto M10 just has to last till then.
m_jermyn
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Post Tue Feb 06, 2018 11:16 am

Hey Brian, Seems it didn't fix it.. Wondering if you can shed some more light?

I can now start the car in any lever position as they bypass worked however I'm still having issues on hot days where it will just not start unless I juggle the shifter and hold it in correct position. Sometimes it won't start at all. In any shift position.

If I wait till it cools down it will start however.

Ignition comes on and I get all dash lights radio everything just no power.

Where should I be looking?

A faulty relay on the shifter wires?

Cheers
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Brianmoooore
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Post Tue Feb 06, 2018 10:53 pm

If you have plugged the two black/yellows behind the glovebox together, then whatever is stopping your engine from cranking on occasions is NOTHING to do with the position of the selector lever, except for the unlikely possibility that moving the lever also moves the whole engine and gearbox just enough to affect a poor connection somewhere.
Open up the diagnostic socket, identify and mark pins 11 and 14. The next time it fails to crank, use a short piece of wire to link these two pins together, which (on a working car) will crank the engine.
Whether it does or not will point to the problem either being with the engine or car body wiring.
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Satan
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Post Tue Feb 06, 2018 11:01 pm

Dodgy earth?

Just throwing it in to the wind.
m_jermyn
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Post Wed Feb 07, 2018 2:17 am

Brian cheers again.

It’s a 84 M10 auto. Will the pins be the same across all models?
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Brianmoooore
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Post Wed Feb 07, 2018 9:45 am

Yours will have the older 'D' shaped socket, but the pin numbers are the same in both that and the later round socket.
m_jermyn
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Post Thu Feb 08, 2018 7:35 pm

Brian...

My D shaped plug has no numbers on it only letters around the outside and nothing in the middle...


Any idea which ones I bridge?


Image
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Brianmoooore
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Post Thu Feb 08, 2018 8:54 pm

http://www.e30zone.net/modules.php?name ... t=#2937664

Seems to have beome mixed with your other thread!
m_jermyn
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Post Fri Feb 09, 2018 6:31 am

Hey Brian,

Success.. Tested in many times today and when it won't start via the key if I turn the ignition on and bridge the pins it fires every time.

So is my problem not in the gear selector but possibly the ignition?
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Brianmoooore
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Post Fri Feb 09, 2018 9:44 am

You now know that the starter motor is cleared of suspicion, and the problem is that the 12 volts+ start signal isn't reaching the engine loom plug from the body wiring.
Likely suspects are the ignition switch itself, the connector half way down the steering column, where the switch loom connects to the body loom (black wire one side, black/yellow the other) and any after market immobiliser, which you may or may not be aware of.
m_jermyn
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Post Fri Feb 09, 2018 9:52 am

No immobilisers or alarms.

Ill have a play with the connector and hope that fixes it..

If not I’ll swap out the switch

Cheers once again Brian. For years you have always had the answers.