fixed illuminated entry

[drtidmore]

I have been living without illuminated entry/display show on entry, since returning my Reatta to service. Wireless remote worked, security system worked, door opening activated interior lights, but NO illuminated entry functionality. I was well aware that splice corrosion under the passenger seat was a widespread root cause of this and other anomalies, but I had already pulled the seat once and verified that there was ZERO indication of water past or present. The BCM handle input diagnostic showed HI with no transition to LO from either door, so it could be a common grounding problem, but that would NOT explain why the wireless remote did NOT trigger illuminated entry (same input on BCM). I could not believe that the BCM itself could be a fault as it was handling all the other interior lighting functions properly.

So I pulled the passenger seat and carpet back and I cut the S304 grey wire splice apart. Knowing that the BCM was looking for path to ground to indicate door handle lift, I proceeded to try grounding each wire. I quickly found the one to the BCM as it powered up the interior lights and they stayed on for the typical illuminated entry period, which vindicated that BCM.

Then I temporarily connected each of the remaining wires, one at a time, to the BCM input wire. I found the driver's door handle was working properly. With two wires remaining, I connect one of them to the BCM input and it immediately caused the BCM to go into illuminated entry mode...not good. As it was easy enough to see if the wire seemed to be running to the passenger door, I discovered it indeed did and there appeared to be either a short in that wire or the handle switch is at fault. The remaining wire was indeed to the wireless remote and connecting it to the BCM resulted in proper operation of illuminated entry when disarming or pressing the interior illumination button on the remote.

So the lesson from this is that if there is a short in the S304 circuit (door handles, wireless remote, BCM illuminated entry input), the BCM will falsely indicate that the input is set to HI and illuminated entry/display show on entry will NOT function.

At the moment, I just left the passenger side door handle wire disconnected until I can tear into the door and further investigate the door handle switch and its associated wiring. Nice to have illuminated entry working once again. Another gremlin off the list even if the root cause still needs further investigation.

[fjr48]

I really appreciate this post. I used this information and got the display on entry working on my 1988 Reatta. I disconnected the passenger side door handle switch at the harness connector inside the door and the system began working properly off the drivers door switch. The passenger side switch shows continuity all the time regardless of door handle position. The diagnostics in the Service Manual does not list this as a possible cause for no display on entry. The actual problem is in the passenger door handle switch, attached wiring or its mounting. Having changed these switches before, for now I will just leave it disconnected. A big thank you to drtidmore for taking the time to share this information.

[drtidmore]

Fjr48,

You mention that you have previous experience with changing out those door handle lift switches. Having surveyed that terrain while replacing the window lift motor on the passenger side and a complete removal to clean and grease the latching mechanism on the driver's side, getting to the little switch looked like a real pain. Could you share what you learned from your previous experience? I suspect that the problem we are both having on the passenger door is a stuck switch. I would love to figure out a way to attempt to free up the switch and lube without removing it, but given its location that may not be possible.

[Guest Mc_Reatta]

Fjr48,

You mention that you have previous experience with changing out those door handle lift switches. Having surveyed that terrain while replacing the window lift motor on the passenger side and a complete removal to clean and grease the latching mechanism on the driver's side, getting to the little switch looked like a real pain. Could you share what you learned from your previous experience? I suspect that the problem we are both having on the passenger door is a stuck switch. I would love to figure out a way to attempt to free up the switch and lube without removing it, but given its location that may not be possible.

DavidT, there was a good thread on this a while back. I'll try to post a link when I can get the search function to respond to my query.

[Guest Mc_Reatta]

Here's a link to a thread discussing the handle:

http://forums.aaca.org/f116/89-outside-door-handle-broken-350163.html

And here's a link on how to get at the handle:

http://forums.aaca.org/f116/exterior-door-handle-replacement-357146.html

[fjr48]

The only way I could replace the switch was to remove the door trim,rear glass run channel and the door lock module assembly. It is in a difficult spot for me to work. This is one of those jobs that the more nimble you are the better.

[drtidmore]

Thanks for the info. Still debating on whether to tackle this near term or add it to the gremlin list for future action. The lack of passenger side activation of illuminated entry/display on entry is certainly not a critical issue nor one that requires immediate action.

I do have one question regarding the actual switch. After reading the posts, I understand that it is simple magnet reed switch (makes sense as they are impervious to moisture). Does anyone know of a source for these switches separate from a complete salvaged handle? I don't want to tear into the door and remove the handle without the parts on hand to fix it. From the pics, the reed switch appears to be a proprietary packaged part, correct?

Edited November 22, 2013 by drtidmore (see edit history)

[drtidmore]

I just PMed my3Buicks as he had recent experience with replacing a broken door handle on his Reatta. He came up with what certainly appears to be a better approach than the FSM method that requires removal of the door latch mechanism. He removed the rear window channel and the topside rubber window sweeper section which allowed him to go in from ABOVE with a small ratchet. This approach would seem to take the majority of the frustration out of the process. Now to find a replacement switch before I tear into this.