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jmjp5055

LED conversion

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2 hours ago, jmjp5055 said:

No wiring involved, changing out the bulbs is easy but getting to some of them you need an engineering degree 😂

That's great, thanks.  Our cars are twinsies, well mine's a coupe, a 91, but white with red interior, so maybe not but close enough!

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I've had my share of backfeed weirdness from changing them out.  Right now I just discovered that my front marker lights are coming on when I hit the brakes, and the left turn signal stops flashing also when I hit the brakes.  I did the ones in the cluster, and all the backlights were fine but when I did the warning lamps they were on at a low glow when the headlights and markers were on.  Had to go back to incandescents for all the warning indicators but kept the CHECK GAGES, turn signals, low fuel warning and HI beams as LED.  I'll still have to undo some more, because something in the brake circuit is backfeeding.  I would check everything in the dark, preferably with a helper while you hit the brakes, before you put it all back together and call it good.  I also found out the hard way that replacing the CHMSL bulbs will freak out the ABS computer.

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On 9/18/2018 at 1:38 AM, crazyd said:

 I also found out the hard way that replacing the CHMSL bulbs will freak out the ABS computer.

I've had an abs code with the factory bulbs before because they were making poor contact due to the sun expanding the connector cavity on the CHMSL. Once I fixed that, no more abs light/fault.

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If something acts up with LEDs it's easy eenough to wire some resistors in parallel with them to match the current draw, futile because that undermines the efficiency of going LED so an electronic flasher is a better plan.

Some of the bulbs in the front will misbehave, as I said before because there are conditions where they work opposite polarity. 

My fix was to substitute the bulb with a little Omron relay to turn the LEDs on.

LEDs do not "backfeed", in circuits where that seems to be the problem it's actually lack of "backfeed" -or- inability to flow both directions rather.

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Update 

changed out high mout brake lights from halogen to led wasn’t that difficult , I’m posting pics, hardest part have to file a 1/2 mm. Notch, on top and bottom of light port, also replaced O rings

 

 

396427B6-E78E-41AA-BE47-C6C1B9F9B242.jpeg

FAA2B97F-13F0-4998-9EC9-EB2B9EC69378.jpeg

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01CC2F5D-88A2-4494-8161-709BE1D1ED81.jpeg

AB15D466-FA99-40EE-927F-0F9E6E5C2DC5.jpeg

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On ‎9‎/‎27‎/‎2018 at 1:42 AM, mfewtrail said:

I've had an abs code with the factory bulbs before because they were making poor contact due to the sun expanding the connector cavity on the CHMSL. Once I fixed that, no more abs light/fault.

I have an ABS light on in my CS. Found two burned out bulbs and one missing entirely in the CHMSL. Fixed that but ABS light is still on. I could have the same problem you have. How did you know the bulbs were making poor contact? Did they not come on?

Edited by James Robert
more clear

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12 hours ago, James Robert said:

I have an ABS light on in my CS. Found two burned out bulbs and one missing entirely in the CHMSL. Fixed that but ABS light is still on. I could have the same problem you have. How did you know the bulbs were making poor contact? Did they not come on?

If your CHMSL brake lamps actually light-up, you shouldn't have the same issue I did.

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7 hours ago, mfewtrail said:

If your CHMSL brake lamps actually light-up, you shouldn't have the same issue I did.

OK, thanks. They do all light now. I just thought yours may have been an intermittent issue. The GM dealer wants $150 to scan for ABS codes. I'm thinking about just buying the scan tool and the adapter cable.

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15 hours ago, James Robert said:

OK, thanks. They do all light now. I just thought yours may have been an intermittent issue. The GM dealer wants $150 to scan for ABS codes. I'm thinking about just buying the scan tool and the adapter cable.

Keep an eye out on ebay for an OTC ABS Reader - part # 3757 or 3758. Both include the scan tool, just one part number denotes that the tool comes with a case if I recall correctly.

 

https://www.ebay.com/itm/OTC-3758-SPX-OTC-ANTI-LOCK-BRAKE-SYSTEM-SCAN-TOOL-Reader/163057194606?epid=1722255754

 

That one doesn't appear to have any cable adapters, so you'll need OTC # 212633 gm adapter - about $10 shipped on ebay.  All together, you could have the tool for half of what GM wants to scan it.

Edited by mfewtrail

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6 hours ago, mfewtrail said:

Keep an eye out on ebay for an OTC ABS Reader - part # 3757 or 3758. Both include the scan tool, just one part number denotes that the tool comes with a case if I recall correctly.

 

https://www.ebay.com/itm/OTC-3758-SPX-OTC-ANTI-LOCK-BRAKE-SYSTEM-SCAN-TOOL-Reader/163057194606?epid=1722255754

 

That one doesn't appear to have any cable adapters, so you'll need OTC # 212633 gm adapter - about $10 shipped on ebay.  All together, you could have the tool for half of what GM wants to scan it.

Tempting. I'm still confused on which OBD I have in my '95. I have a 12 pin plug mounted on the lower dash, with only two wires going into it, but hanging free under the dash I also found a 16 plug connector. Does that make a difference?

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On 10/12/2018 at 12:38 PM, James Robert said:

Tempting. I'm still confused on which OBD I have in my '95. I have a 12 pin plug mounted on the lower dash, with only two wires going into it, but hanging free under the dash I also found a 16 plug connector. Does that make a difference?

It doesn't make a difference to that OTC tool I linked to. It will read 94-95 w-bodies and pre-94 with the same cable adapter.

 

edit: I read over this quickly Saturday and somehow missed the part about both data connectors. I probably just assumed you didn't know if a OBD-1 scan tool would work on a 94-95 because people like to call them "obd 1.5."  I said they would read either with the same cable because "1.5" w-bodies should have the 12 pin connector standard. I don't recall ever seeing a 16 pin connector in  a 95. Maybe your car is a transitional period 95  or either someone added it like Imp558 suggested.  Are you certain you have a 1995? What's the build date on the car?

Edited by mfewtrail

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Replying to let you know I edited my post above(not sure we receive reply notifications for edited posts).  Going back through old posts on the site, it appears others with 95's have had the 16 pin style connector as well. I however did not see anyone posting about having both connectors though which leads me to believe that was added by someone. I'm not sure what to tell you about that OTC scan tool now unless the OBD-II adapter cables will work for it. I have an OBD-II adapter cable for my OTC tool, but I don't know it it came with my ABS reader or my "mind reader" powertrain scan tool. The cable adapter has a port where it looks like it would take jumper keys or something similar to the ones older snap-on tools used. I didn't receive any keys with it and it's hard to find any documentation online for these old ass tools.

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