Auto Selector light issue (pics)

[Canonite]

Here's a strange one for the experts.
My V6 auto selector started on occasion displaying an illuminated Drive and Neutral at the same time.

See below:



When this happens the IPK doesn't display that any gear is selected.
When I do select Drive, it is 100% absolutely in Drive, despite the indicated D/N on the selector and IPK not displaying anything. The car drives spot on and despite this issue, there are no issues with the way the car engages gears, nor with the way it changes up and down the range.

At first I just thought I had placed the lever in between gears, so i'd move it into 4th, then back to Drive and it would then remain indicated, solely in Drive.

What started out as an occasional thing gradually got worse, so it has developed now so that whenever Drive is selected, although the gearbox is mechanically 100% in Drive, the selector displays both Drive and Neutral illuminated, and IPK doesnt display that is is in gear.

I'm convinced this is not a mechanical thing, potentially an issue with the wiring. The lever feels precise and as I said above, the gears engage and perform perfectly.

So... any ideas?

[Maxfly]

Not sure how this works but assume there’s a sliding contact between the gear lever and that indicator? Would start by stripping it down and cleaning up that switch. My guess is because the indicator has 2 lights showing the IPK doesn’t know which one is correct so defaults to showing hee haw?!?

[Simondi]

Just looking through the tech help and noticed this thread. May be of use

[Canonite]

Originally Posted by Maxfly

Not sure how this works but assume there’s a sliding contact between the gear lever and that indicator? Would start by stripping it down and cleaning up that switch. My guess is because the indicator has 2 lights showing the IPK doesn’t know which one is correct so defaults to showing hee haw?!?

Clean which switch? The inhibitor switch on the gearbox or the actual selector switch pictured?

Originally Posted by Simondi

Just looking through the tech help and noticed this thread. May be of use

The selector still illuminates in the gears.
Gears 4, 3, 2, N and P all illuminate properly when selected.
The issue is that when D is selected, both N and D are illuminated which also means the IPK doesn't display any gear.
The gears all engage perfectly and shift without any effort so im sure the gearbox is fine.

[SD1too]

Hello Al,

The traditionally named "inhibitor switch" on this electronically controlled automatic gearbox actually contains eight switches. Five of these provide a 12v supply to the transmission ECU when the selector lever is in positions N, D, 4, 3 and 2.

Additionally there is a splice in each of these wires which is connected to the LED display next to the selector lever.

The transmission ECU sends the currently selected gear to the instrument pack display via the CAN bus.

You're right Al that this is a strange fault. I think I'd begin with the selector ("inhibitor") switch to see if the N and D switches* really are closing at the same time. If so, check the adjustment of the selector cable.

I hope this helps.

Simon

* The N output is on pin 2 (green) and the D on pin 1 (green/black).

[Canonite]

Originally Posted by SD1too

Hello Al,

The traditionally named "inhibitor switch" on this electronically controlled automatic gearbox actually contains eight switches. Five of these provide a 12v supply to the transmission ECU when the selector lever is in positions N, D, 4, 3 and 2.

Additionally there is a splice in each of these wires which is connected to the LED display next to the selector lever.

The transmission ECU sends the currently selected gear to the instrument pack display via the CAN bus.

You're right Al that this is a strange fault. I think I'd begin with the selector ("inhibitor") switch to see if the N and D switches* really are closing at the same time. If so, check the adjustment of the selector cable.

I hope this helps.

Simon

* The N output is on pin 2 (green) and the D on pin 1 (green/black).

Is this on the gearbox?
I had to have my battery replaced about a month ago as it was leaking fluid from the ventilation port. All the battery tray had corrosion. I cleaned it up when the battery was swapped.
Is there a potential link to any wiring under the battery tray being compromised while this was leaking?

[trikey]

That would be the place to look then! Whip the battery tray off and clean around the abs plug before the corrosion eats it away, you really don’t want to be having to rewire one of those!!

[SD1too]

Originally Posted by Canonite

Is this on the gearbox?
Is there a potential link to any wiring under the battery tray being compromised while this was leaking?

Yes and very possibly!

Simon

[COLVERT]

Warm water will wash away any acid.

If the battery was leaking acid through the vent then the usual cause of this is over charging.

Would be wise to check the voltage at the new battery terminals with the engine ticking over. Should be between 14 to 14.5 volts approx.

[Maxfly]

Originally Posted by Canonite

Clean which switch? The inhibitor switch on the gearbox or the actual selector switch pictured?



The selector still illuminates in the gears.
Gears 4, 3, 2, N and P all illuminate properly when selected.
The issue is that when D is selected, both N and D are illuminated which also means the IPK doesn't display any gear.
The gears all engage perfectly and shift without any effort so im sure the gearbox is fine.

My thoughts were the actual selector switch pictured but it looks like wiser than me have given more likely ideas that may sort this