nascarlady Posted December 18, 2023 Share Posted December 18, 2023 We need your help. Our 1989 Reatta suddenly developed a problem that the instrument panel was not showing the mileage, etc. I pulled the Cluster and sent it to Cluster Fix. They checked it out and found a couple of minor items and fix them but said that doesn't fix the dark panel. They said the problem was that the input coming from the BCM that causes it to turn on is not going Plus. I told the glove compartment and checked that signal on the dark blue/orange wire it was not going Plus. Then I used the CRT to read the codes. It showed the code BD 552 memory reset indicator. I went ahead and purchased a new BCM, but I have not replaced the BCM since there may still be some other issue such as connectors getting intermittent. Questions: How do I remove those connectors? How do I use the CRT to clear the BCM codes? What are other things that I should try? Link to comment Share on other sites More sharing options...
2seater Posted December 19, 2023 Share Posted December 19, 2023 I looked in the How To Guides at the top of the page and did not see specific instructions for removing the BCM. There are three large harness connectors facing you after you remove the glovebox. They are like most connections under the dash where the connector latch needs to be released as you pull the plug out. The instructions for resetting codes for everything in the diagnostic system is located under the Diagnostic tab at the top of this page. There is a copy of the 88-89 diagnostic booklet which contains all of the instructions, including clearing codes. 2 Link to comment Share on other sites More sharing options...
Ronnie Posted December 19, 2023 Share Posted December 19, 2023 3 hours ago, nascarlady said: It showed the code BD 552 memory reset indicator. If that is the only code you are getting it's not an indication of a problem with a bad BCM. That code can be set by just disconnecting the battery. 2 1 Link to comment Share on other sites More sharing options...
DAVES89 Posted December 19, 2023 Share Posted December 19, 2023 I would start with pulling the plugs, cleaning them with contact cleaner and reconnecting them. Just last summer I had a problem with the A/C always blowing cold because the actuator wasn't being told to close the door to the desired setting. I pulled the plugs on the BCK+M sprayed them and reconnected them. Then it worked. Keep in mind you have a 35 year old car and the connections sometimes lose the conductivity. 1 1 Link to comment Share on other sites More sharing options...
nascarlady Posted December 19, 2023 Topic Author Share Posted December 19, 2023 Thanks for the good suggestions. Link to comment Share on other sites More sharing options...
Anthony Posted December 24, 2023 Share Posted December 24, 2023 (edited) IPC is completely blank? Service manual says to check pins LTE, RTG, RTH, RBA, RBB, RBC, RTD at the IPC connector. Wake-up curcuit pin RBH is not mentioned as part of this diagnosis. It is part of a separate function called Display on Entry, that turns it on for only 20 seconds when you first get into the car and close the door. Edited January 12 by Anthony Link to comment Share on other sites More sharing options...
Anthony Posted December 24, 2023 Share Posted December 24, 2023 LTE B+ RTG gnd RTH 7V RBA B+ RBB B+ RBC gnd RTD gnd All tests to be performed with ignition in Run Link to comment Share on other sites More sharing options...
nascarlady Posted January 12 Topic Author Share Posted January 12 Anthony, thank you for the good info. Question -- Is there a crossover to show the connector pin numbers? General update on troubleshooting for blank Instrument panel -- Now we have replaced the BCM with a new BCM, but still no wake-up to the IPC. The car is running fine, except the A/C compressor needs to be replaced. The CRT and BCM test codes are showing warnings. Is it possible that the BCM is blocking the wake-up to get the driver's attention? Link to comment Share on other sites More sharing options...
Anthony Posted January 12 Share Posted January 12 4 hours ago, nascarlady said: Is there a crossover to show the connector pin numbers? These are views of the socket half of the connection. 2 Link to comment Share on other sites More sharing options...
nascarlady Posted January 12 Topic Author Share Posted January 12 Anthony, thanks for the cluster connector info. 1 Link to comment Share on other sites More sharing options...
nascarlady Posted January 13 Topic Author Share Posted January 13 Anthony, We checked the power and ground pins on the cluster connector. They were all fine, but pin H for wake-up from the BCM never goes up. General question to the Forum: Update on troubleshooting for blank Instrument panel -- Now we have replaced the BCM with a new BCM, but still no wake-up to the IPC. The car is running fine, except the A/C compressor needs to be replaced. The CRT and BCM test codes are showing warnings. Is it possible that the BCM is blocking the wake-up to get the driver's attention? Also, does anyone have a recommendation for a technician/shop in the San Jose, CA, area? Link to comment Share on other sites More sharing options...
Anthony Posted January 14 Share Posted January 14 When you say pin H does not go up, do you mean RBH or RTH? Link to comment Share on other sites More sharing options...
Anthony Posted January 14 Share Posted January 14 For better understanding of the problem, we need to know that there are two wake-up circuits from the BCM: One circuit turns on the Vacuum Fluorescent (VF) display for 20 seconds when the door is opened, and then shuts off. The VF display is only the upper part of the IPC that has speedometer, mileage, etc. That circuit ends at cavity RBH. The other circuit comes on when the ignition is on. But it doesn't go directly to the IPC. It first wakes up the Central Power Supply (CPS), which then sends 7 volts to the IPC. That circuit ends at cavity RTH. My first question was- is the IPC completely blank? I mean the VF display (mileage, speedometer) and the indicator lights (brake, service engine soon, etc.) across the bottom as well. By blank, I mean no dashes, no lights, nothing. If the IPC is completely blank, then the VF wake-up circuit is not the problem. If it is partially lit, then we need to know what is lit and what is not. If all the powers and grounds mentioned in my previous post tested correctly, and the connection is good, then pushing the TEST button on the IPC with the ignition in Run should light everything up in sequence. Link to comment Share on other sites More sharing options...
Ronnie Posted January 14 Share Posted January 14 On 1/11/2024 at 7:38 PM, nascarlady said: The CRT and BCM test codes are showing warnings. What are the codes and warnings? Link to comment Share on other sites More sharing options...
nascarlady Posted January 14 Topic Author Share Posted January 14 Anthony, thank you for the good suggestions that you are providing. Our test results: With the doors closed and key off -- no lights Then with key on -- Lights on > service check, battery, water. Lights off>temp, anti-lock, brake, security, no lights above. Then, with TEST pressed --Llights on > service check, battery, water, temp, anti-lock, brake. Lights off> security, no lights above. Ronnie, CRT shows A/C compressor disengaged. Test codes show B447 Very Low A/C Refrigerant Condition Warning / A/C clutch Link to comment Share on other sites More sharing options...
Ronnie Posted January 15 Share Posted January 15 I think the IPC should light up when you press the TEST button regardless of what the BCM is doing. Seems to me like a test button that is part of the IPC should override all external inputs assuming the IPC has power going to it. I don't have a way of doing any testing anymore or I would unplug the BCM and see if the test button still lights up the fluorescent display to prove the IPC is most likely the problem. Here is the bottom line for me... Don't just assume that Cluster Fix knows what they are talking about. If the IPC doesn't pass the test below, taken from the '89 FSM, buy or borrow an IPC that you know is in good working order from someone you can trust and see if that fixes your problem. Never hurts to have a spare IPC anyway. 1 Link to comment Share on other sites More sharing options...
nascarlady Posted January 16 Topic Author Share Posted January 16 Ronnie, thanks for the TEST button check. We did the check, and none of the fluorescents turned on. Also, we used a voltmeter to confirm that the 7-volt power pin is right on 7.0 volts. Please suggest a technician/shop where we can buy a Cluster. Link to comment Share on other sites More sharing options...
Ronnie Posted January 16 Share Posted January 16 Jim Finn, reattas60@gmail.com, has been in the used Reatta parts business for many years. I have purchased parts from him several times. He has fair prices and he is honest. 1 1 Link to comment Share on other sites More sharing options...
nascarlady Posted January 20 Topic Author Share Posted January 20 Thanks for the suggestion. I'm waiting to hear from Jim if he has an IPC available. 1 Link to comment Share on other sites More sharing options...
nascarlady Posted February 7 Topic Author Share Posted February 7 The IPC that was repaired by Cluster Fix did not work. The upper light portion would not turn on when pressing the TEST button. So, I ordered an IPC from Jim Finn. I unplugged the IPC from Cluster Fix and plugged in the one sent by Jim, and it worked like a charm. 3 Link to comment Share on other sites More sharing options...
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