AustinJohn

I know the 1984 to 1989 models used a courtesy lights delay timer. Some Forum threads refer to one for the 1994 but I do not believe models after 1990 had one. Am I right or wrong?

Many thanks!

John

RollaMo-LT4

Not sure if it's the same type or not, but they still used a "delay" feature.
When you shut the door, the interior lights remain on for a few seconds before fading out.

Even if you leave the door open (at least on the '96), the interior lights will go out after about 15 minutes

84vette96

I may be wrong, but I think the 94 had a ccm like the 95 and 96 that controls the dimming. If the door switches work they should send the signal to the ccm , open or closed. the rear glass on a cope should only turn on rear courtesy lights.

AustinJohn

Yes, that's how mine work. What confuses me is all the vendors sell '84-'89 delay timer modules and circuit boards but none for the later years and I can't find any reference to it in my '94 FSM (my '85 FSM calls it a "dome light delay timer".)

John

AustinJohn

You're exactly right! And using the wonders of google I found an old Corvette Fever article relating to the issue which I'm going to include in full just in case it helps anyone in the future.

John

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Question: I have a '92 Corvette coupe. I am having a problem with the interior lights staying on. The door-ajar light on the instrument panel is not coming on, and the lights still stays on. The only way to turn them off is to pull either the courtesy fuse or the LED fuse. I have tried to push the door switch all the way in on both doors to no avail. Is there an auto dimmer that may be bad or some other component I am missing? Any help will be appreciated.
Ilm Via e-mail

Answer: The '90-'96 Corvette courtesy lights are controlled by the CCM (central control module) located in the dash behind the radio receiver. The courtesy lights are set-up with a delay when entering or exiting the passenger compartment; The courtesy lights are also designed to turn off after ten minutes when the doors are left open to avoid battery drain. If the doors are opened and closed in the ten-minute time period, the timer starts all over again. Courtesy lights should not come on at any time when there is enough ambient light available to satisfy the light sensor in the dash. The light sensor is located in the DIC (driver information center) at the upper left corner. Courtesy light on input signals come from the door ajar switches, door lock key switches (when going from the locked position to unlocked), headlight switch (moving the instrument cluster dimmer switch to the top), and the ambient light sensor. Once the CCM gets a signal from a door lock key switch, it processes the info and then latches a courtesy light relay located behind the passenger side of the dash, but only if the ambient light sensor senses low-Iight conditions for illuminated entry. If the door was unlocked upon entering, the door ajar switches provide info to the CCM with- out involving the door lock switches. The ambient light sensors come into play after input from the door ajar and lock switches. After 1992, the PKf {passive keyless entry} system became involved with the courtesy light. The PKf signaled the CCM that the door was unlocked and the courtesy lights should be on in low ambient light conditions. Beware! This same situation may apply if an aftermarket alarm system was installed on a '90-'92 Corvette. If you have an aftermarket alarm system, check there first.

Now that we have an idea how the system works, let's see if we can figure out what's causing the problem. The first place to check is the CCM for possible codes relating to the problem. You can enter diagnostic mode by grounding terminal G to A in the ALDL {assembly line diagnostic link} connector under the driver-side dash panel. The ALDL points downward and is about where your right knee would be while seated in the driver seat. ALDL Terminal A is at the top right corner and terminal G the lower left corner. Use a jumper wire to connect terminals A to G, and then turn the ignition switch to the ON position. When the key is turned on, fault codes will be displayed automatically in the speedo LCD screen. The module number will be displayed in the left center of the LCD starting with mod- ule 1, which is CCM data. The next module displayed will be 4 fCM {engine control module} codes and finish with module 9 displaying ABS/ ASH {antilock brake system/acceleration slip regulator} and fBCM {electronic brake control module} codes. The codes will have an "H" for history codes and "C" for current codes, meaning the problem is occurring right at that moment. After any codes are displayed for a module, the screen will display ,,-- " ending that module interrogation and going on to the next module. If you miss the codes the first time, you can turn the ignition key off and then back to the on position and the codes will display again in the automatic sequence as long as the jumper wire is in place on the ALDL. There is also no limit to the number of times the codes are displayed.

Once you interrogate the CCM, you may find code 24, indicating a shorted courtesy light relay coil or CCM internal open circuit or code 25, which is a courtesy lamp relay coil circuit open or shorted to ground in the CCM. If you find a code, make note of it, then you can select the CCM cycle inputs function by repeat- edly pressing the TRIP/ODO button in the DIC until "1.3" is displayed in the trip monitor area of the speedo LCD screen after the automatic code sequence has finished. Once you're there, press the ENG/MET button until "04" is displayed in the odometer area of the LCD. This is the right door ajar input. If you pass "04," you can go back by pressing the FUEL INFO but- ton. When the door is opened, "I" should be displayed in the LCD odometer area and then "0" when the door is closed. If the door is open when you start interrogating the system, "I" will be displayed and then "0" when closed. After testing the right door ajar, go to "05" left door ajar and do the same test. This will tell you if the door switches are working properly; and if the CCM is processing the info correctly. If the correct info is displayed, the door switches, wiring, and CCM is processing the info correctly.

The most likely problem is a malfunctioning door lock key switch, especially if it's used often. There will be no code for this problem, but can be tested while performing the input tests. Go back to test 1103'1 in the input tests. A "0" should be displayed until the door key is inserted and turned to the unlock position. The display should be showing a "1" in the unlocked position then back to "0" when the key is centered in the door lock. If the display shows "1" all the time, you have found the problem. The door panel will require removal and door lock cylinder key switch replacement.

If that didn't fix the problem, the next step is to see if the courtesy lights can be controlled by the CCM manually; We can cycle the courtesy lights through the CCM output test. This tests the courtesy light relay operation, wiring from the CCM to the relay and wiring to the courtesy lights. Select the CCM cycle output function by pressing the TRIP/ODO button in the DIC until "1.4" is now displayed in the LCD screen. Once you're there, press the ENG/MET button until 1110'1 is dis- played in the odometer area of the LCD. If you pass "10," you can go back by pressing the FUEL INFO button. When 1110'1 is displayed, the courtesy lights should go on and off in approximately three-second intervals. If the courtesy lamps stay on during testing, I would check the relay under the passenger-side dash for possible sticking contacts. Remove the carpeted lower knee-bolster panel on the passenger side of the dash to access the relays.

The panel on the passenger side of the dash that houses the fuse panel must be removed to remove the lower knee- bolster panel. There is one tmm screw hidden behind the fuse panel bezel for the lower panel. The courtesy light relay would be the second relay from the passenger door side of the dash. There is a bank of five relays attached to a piece of plastic channel that runs parallel with the dash. Once the relay is pulled, the courtesy lights will be off unless the headlight switch is causing the problem. When the headlight
switch instrument dimmer rheostat is in the fully up position, the ground circuit to the courtesy lights is completed, bypassing all of the aforementioned components. All of this info gives you a good idea of what goes on and should point you in the right direction.

If the door ajar info was correct and pulling the relay turns the courtesy lights oft; try a relay. If the relay isn't the problem, the CCM is grounding the relays gray/black striped wire, which could mean CCM replacement. It's difficult to access the relay and even more difficult to check the wiring in the relay socket, but to know for sure that the CCM is the culprit, the gray/black wire would need to be checked for ground. There is a possibility the gray/black wire is shorted to ground between the CCM and courtesy light relay. If the gray/black wire is grounded all the time, the CCM would require access behind the A/C Controller and the radio. At this point, a factory service manual should be used to further test and access the CCM.

MAY 2006 CORVETTE FEVER

pcolt94

MY 94 definitely has a delayed timer for the courtesy lights. Now I am not talking about the delayed bus for the power windows and radio which will turn off when the door is opened.

The delayed courtesy lights work in regard to the light sensor and ambient lighting. If my car cover is on or if it is dark outside, the courtesy lights will delay going off for 15 or so seconds.

However if outside in the daytime and I close the door as I exit, the courtesy lights will go off immediately when the door is closed.

rob-cyn

what makes the tiny little bulbs that are in the orange lens in the door handles come on ? I cant get mine to work.

1800Wing

Mine come on whenever the courtesy lights do, or if I rotate the dimmer switch to full on. 96 Coupe.

later, tiny

0Willcox Corvette

John-

I make the boards for the prior years here in house.. but the reason we don't have anything available for the 90 and new cars is as mentioned above.. They are ccm controlled and there really is nothing there to make.

Believe me, the 84-89 boards we make are the best selling part we have and if there was a way to make something for the newer cars I'd be all over it...


Willcox

AustinJohn

Thanks everybody!

John

illenema

[QUOTE=AustinJohn;1576923916]You're exactly right! And using the wonders of google I found an old Corvette Fever article relating to the issue which I'm going to include in full just in case it helps anyone in the future.

John

---------------------------------------

Question: I have a '92 Corvette coupe. I am having a problem with the interior lights staying on. The door-ajar light on the instrument panel is not coming on, and the lights still stays on. The only way to turn them off is to pull either the courtesy fuse or the LED fuse. I have tried to push the door switch all the way in on both doors to no avail. Is there an auto dimmer that may be bad or some other component I am missing? Any help will be appreciated.
Ilm Via e-mail

Answer: The '90-'96 Corvette courtesy lights are controlled by the CCM (central control module) located in the dash behind the radio receiver. The courtesy lights are set-up with a delay when entering or exiting the passenger compartment; The courtesy lights are also designed to turn off after ten minutes when the doors are left open to avoid battery drain. If the doors are opened and closed in the ten-minute time period, the timer starts all over again. Courtesy lights should not come on at any time when there is enough ambient light available to satisfy the light sensor in the dash. The light sensor is located in the DIC (driver information center) at the upper left corner. Courtesy light on input signals come from the door ajar switches, door lock key switches (when going from the locked position to unlocked), headlight switch (moving the instrument cluster dimmer switch to the top), and the ambient light sensor. Once the CCM gets a signal from a door lock key switch, it processes the info and then latches a courtesy light relay located behind the passenger side of the dash, but only if the ambient light sensor senses low-Iight conditions for illuminated entry. If the door was unlocked upon entering, the door ajar switches provide info to the CCM with- out involving the door lock switches. The ambient light sensors come into play after input from the door ajar and lock switches. After 1992, the PKf {passive keyless entry} system became involved with the courtesy light. The PKf signaled the CCM that the door was unlocked and the courtesy lights should be on in low ambient light conditions. Beware! This same situation may apply if an aftermarket alarm system was installed on a '90-'92 Corvette. If you have an aftermarket alarm system, check there first.

Now that we have an idea how the system works, let's see if we can figure out what's causing the problem. The first place to check is the CCM for possible codes relating to the problem. You can enter diagnostic mode by grounding terminal G to A in the ALDL {assembly line diagnostic link} connector under the driver-side dash panel. The ALDL points downward and is about where your right knee would be while seated in the driver seat. ALDL Terminal A is at the top right corner and terminal G the lower left corner. Use a jumper wire to connect terminals A to G, and then turn the ignition switch to the ON position. When the key is turned on, fault codes will be displayed automatically in the speedo LCD screen. The module number will be displayed in the left center of the LCD starting with mod- ule 1, which is CCM data. The next module displayed will be 4 fCM {engine control module} codes and finish with module 9 displaying ABS/ ASH {antilock brake system/acceleration slip regulator} and fBCM {electronic brake control module} codes. The codes will have an "H" for history codes and "C" for current codes, meaning the problem is occurring right at that moment. After any codes are displayed for a module, the screen will display ,,-- " ending that module interrogation and going on to the next module. If you miss the codes the first time, you can turn the ignition key off and then back to the on position and the codes will display again in the automatic sequence as long as the jumper wire is in place on the ALDL. There is also no limit to the number of times the codes are displayed.

Once you interrogate the CCM, you may find code 24, indicating a shorted courtesy light relay coil or CCM internal open circuit or code 25, which is a courtesy lamp relay coil circuit open or shorted to ground in the CCM. If you find a code, make note of it, then you can select the CCM cycle inputs function by repeat- edly pressing the TRIP/ODO button in the DIC until "1.3" is displayed in the trip monitor area of the speedo LCD screen after the automatic code sequence has finished. Once you're there, press the ENG/MET button until "04" is displayed in the odometer area of the LCD. This is the right door ajar input. If you pass "04," you can go back by pressing the FUEL INFO but- ton. When the door is opened, "I" should be displayed in the LCD odometer area and then "0" when the door is closed. If the door is open when you start interrogating the system, "I" will be displayed and then "0" when closed. After testing the right door ajar, go to "05" left door ajar and do the same test. This will tell you if the door switches are working properly; and if the CCM is processing the info correctly. If the correct info is displayed, the door switches, wiring, and CCM is processing the info correctly.

The most likely problem is a malfunctioning door lock key switch, especially if it's used often. There will be no code for this problem, but can be tested while performing the input tests. Go back to test 1103'1 in the input tests. A "0" should be displayed until the door key is inserted and turned to the unlock position. The display should be showing a "1" in the unlocked position then back to "0" when the key is centered in the door lock. If the display shows "1" all the time, you have found the problem. The door panel will require removal and door lock cylinder key switch replacement.

If that didn't fix the problem, the next step is to see if the courtesy lights can be controlled by the CCM manually; We can cycle the courtesy lights through the CCM output test. This tests the courtesy light relay operation, wiring from the CCM to the relay and wiring to the courtesy lights. Select the CCM cycle output function by pressing the TRIP/ODO button in the DIC until "1.4" is now displayed in the LCD screen. Once you're there, press the ENG/MET button until 1110'1 is dis- played in the odometer area of the LCD. If you pass "10," you can go back by pressing the FUEL INFO button. When 1110'1 is displayed, the courtesy lights should go on and off in approximately three-second intervals. If the courtesy lamps stay on during testing, I would check the relay under the passenger-side dash for possible sticking contacts. Remove the carpeted lower knee-bolster panel on the passenger side of the dash to access the relays.

The panel on the passenger side of the dash that houses the fuse panel must be removed to remove the lower knee- bolster panel. There is one tmm screw hidden behind the fuse panel bezel for the lower panel. The courtesy light relay would be the second relay from the passenger door side of the dash. There is a bank of five relays attached to a piece of plastic channel that runs parallel with the dash. Once the relay is pulled, the courtesy lights will be off unless the headlight switch is causing the problem. When the headlight
switch instrument dimmer rheostat is in the fully up position, the ground circuit to the courtesy lights is completed, bypassing all of the aforementioned components. All of this info gives you a good idea of what goes on and should point you in the right direction.

If the door ajar info was correct and pulling the relay turns the courtesy lights oft; try a relay. If the relay isn't the problem, the CCM is grounding the relays gray/black striped wire, which could mean CCM replacement. It's difficult to access the relay and even more difficult to check the wiring in the relay socket, but to know for sure that the CCM is the culprit, the gray/black wire would need to be checked for ground. There is a possibility the gray/black wire is shorted to ground between the CCM and courtesy light relay. If the gray/black wire is grounded all the time, the CCM would require access behind the A/C Controller and the radio. At this point, a factory service manual should be used to further test and access the CCM.

MAY 2006 CORVETTE FEVER[/QUOTE
Information available here amazes me