Ronnie

Your response seems to be Elementary, my dear Watson. <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" /> It appears you have not carefully read this entire thread. I determined that the photocell needed replacement. But I choose to bypass the photocell (see post above) in order to keep from breaking the grille cover. After that is when I started to investigate the dimming problem. The facts speak for themselves as to whether of not spraying with WD40 works or not. I went from the dashlights and crt not dimming at all when the headlights or parking lights were turned on, to them working perfectly after two sprayings with WD40. I don't see how you can disagree with that at all. As for the photocell being the problem, it was disconnected and replaced by the proper resistor to simulate a dark condition at all times to the BCM before I started troubleshoting the dimming problem. Therefore the photocell could not have been, and is not currently, working erratically. I believe the problem WD40 may correct, is more of a sticking problem in the switch than a dirty contact problem. The switch now feels more crisp when the buttons are pushed and it seems to snap on and off. One thing is for sure, spraying with WD40 (no contact cleaner), as Howard and others have suggested, definitely worked for me. Thanks to everyone for all your help!

Just a reminder to anyone who has not done leakdown testing before. Leadown testing should be done with safety in mind. Applying high pressure to a cylinder a few degrees off TDC can cause the engine to turn unexpectedly when the pressure builds up and overcomes internal friction/resistance of the engine. Injury can come from tools (such as socket and rachet) used to turn the crankshaft or hands caught in belts while trying to turn the engine.

Thanks for all the help. You guys saved me the cost of a new switch. After one cleaning my headlight switch is back to almost 100%. It is still sticking a little. I'm going to give it another cleaning tomorrow if it still sticks after soaking over night. I love this forum!!

Thanks for your advice Howard. I'm going to give it a try tommorrow. I think that will probably fix it. I have found that the crt and the dash lights will dim sometimes when I turn the lights on and off repeatedly. Makes sense that a dirty headlight switch would be the problem. I had the problem with the photocell also. To fix it, I removed the glove box and disconnected the wht/blk wire at BCM connector 3D8. To prevent getting a code B119, I installed a resistor (either 200k or 2 meg, I have forgot) between the BCM connector 3D8 and the BCM ground terminal. It worked great after that when I turned on the fog lights but still would not dim when turning on the park or headlights. So now I'm troubleshooting the light switch. I know it would have been better to replace the photocell but I didn't want to take a chance of breaking my dash pad or the defroster grille. Both of them still look like new.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I just sprayed tuner cleaner and lubricant in the cracks - mine has worked fine since. </div></div> Do you mean spray it all around the buttons and sliders without removing the switch panel?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">That is usually caused by a dirty headlamp switch. </div></div> I have been working on it today and have found that sometimes it will work when pushing the parking light button on the headlamp switch. Can you tell me how to go about removing it and cleaning it. Any help would be appreciated...Thanks!

Which circuit tells the BCM to dim the dash lights and CRT when the lights are turned on? Is it one coming from the headlights? Parking lights or what? My dah lights and crt only dim when the fog lights are on. Thanks!

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">As simple as adding a single high current diode. You can also use a relay but that would be more complex. </div></div> Where (which wires and their location) would I add the high current diode and where can I get one? Thanks for your help but I need more information in order to do the job. Thanks!

Is there an easy way to do this?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Any chance of taking this one step further??? My dashlights dim like they are supposed to....but my climate control and radio do not dim at all. Any comments or suggestions? Dave </div></div> I didn't want to take a chance on destroying my dash panel and defroster grill so I disconnected the wht/blk wire at BMC connector 3D8. Now everything dims a expected as long as the fog lights are on and the headlights are on low. If I turn the fog lights off or turn the headlights on bright the crt and speed display go to full bright. I suspect a headlight switch problem still exists but I'm not ready to spend the big bucks to replace it right now. I like the fog lights on all the time anyway, so how can I have the fog lights stay on, even when the headlights are on bright? That would keep the dash and crt lights dim? Maybe a relay I could unplug or something? If I could do that I would be a happy camper and keep and extra $180 bucks for the headlight switch in my pocket for more pressing problems. Any ideas anyone?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">First turn your fog lights on while in the garage or a darkened area. Did the panels dim ? If so the problem is in the headlamp switch. The photocell reading is also one of the diagnostic displays (BD-44 - 0%=daylight and 100%=dark) </div></div> Turning in the fog lights did not dim the panels. One thing I have discovered on the headlight switch, is the dimmer slider feels sloppy and vague. Is that normal or do I have a problem with the dimmer slider? I checked BD44 and it varies from 48% (garage lights) to 61% (completley covered). Is there anyting else to check before replacing the photocell? I'm getting code B123 (Panel lamp enable circuit problem) is that caused by the photocell or is that a different problem? I also get a B552 (BCM Memory Reset indicator) What is that telling me? Thanks to everyone for your help so far!

Where is a good place to purchase the accumulator and get a good price?

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I have a 90 Reatta that when I turn on the head lights the dash lights will not dim, I replaced the switch with a known good one from another Reatta and that didn't work either, any clues where to turn next? </div></div> I have just purchased an '88 model with the same problem. Could someone please tell me how to get to the photocell and how to test it. My CRT diagnotics tells me "Darkness needed..." when I try to adjust the brightness so I suspect the photocell. I would appreciate any help.

I just purchased a 1988 Reatta. I think I will like it although it has some problems. The first problem that I need to fix is the brakes. The yellow and then the red lights come on each time the pedal is pressed. I took the brake test and the results are as follows: Test 1 - 1 Test 2 - 7 Test 3 - 20 yellow 20 red Test 4 - 20 (The pump did seem to slow slightly at the end before the pump shut off) Test 5 - 1 ( tested numerous times) Test 6 - 3/4 inch Test 7 - Did not feel tap or hear a thump Is a replacement of the accumulator is order? It seems it would be from the test results but I would like the opinion of someone who has been down this road before. Can the accumulator affect the test 7 results for the main valve operation? Any and all help is appreciated!