Need help electrical problem! bcm? ecu?
Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
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From: Arizona
Need help electrical problem! bcm? ecu?
Hello everyone first post ever, always loved the site I used it all the time to do my research and homework. Recently i have been haveing electrical problems that point to either the BCM number #2 or ECU. I have checked all the fuses and they all look good the wireing for everything still looks good but here are my only symptoms and they all happen at the same time at random.
1- Thermostat works intermittent, off and on
2- Blower motor for a/c turns off and on
3- Instrument cluster freezes but never rpm,speedo,or gas gauge.
4- Door lock actuator button doesnt work
5- Drivers side window switch only works no other windows can be controlled from the panel
6- steering wheel doesnt retract or come back down on its own sometimes
7 ish- automatic shift lock release doesnt work idk if its related but just adding incause.
radio always works and everything still displays on a/c panel and the car feels great no mecanical issues so far. if you need more info just let me know i have to take a trip to califormia very soon and am debateing on if i should fix it now or after. money kind of a issue but if i need to get fixed asap i can figure something out.
Thankyou very much for any help.
Lexus gs 300 1999
1- Thermostat works intermittent, off and on
2- Blower motor for a/c turns off and on
3- Instrument cluster freezes but never rpm,speedo,or gas gauge.
4- Door lock actuator button doesnt work
5- Drivers side window switch only works no other windows can be controlled from the panel
6- steering wheel doesnt retract or come back down on its own sometimes
7 ish- automatic shift lock release doesnt work idk if its related but just adding incause.
radio always works and everything still displays on a/c panel and the car feels great no mecanical issues so far. if you need more info just let me know i have to take a trip to califormia very soon and am debateing on if i should fix it now or after. money kind of a issue but if i need to get fixed asap i can figure something out.
Thankyou very much for any help.
Lexus gs 300 1999
Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
Likes: 0
From: Arizona
I thought when you change the main computer, witch is the ecm or ecu? That your not able to start the car the key has to be reprogrammed some how? I read also that some people have just turned the key back and forth until it just turned on. But everything I've mostly read also points to a bad body control module. Maybe I'll swap that one first if I can too see if it's it. Hopefully my uncle still has his gs hah.
If you find someone with the same car you swap computer and put his fob close to ignition switch and start the car with your key. The chip is in the fob not the key. If it is the computer when you buy a used one make sure you get it with the master fob. Then you just switch the fob in your key. Once you do that you can easily add new keys
By the way changing the main computer is a 5 minute job much easier than the body ones. I would try that first if you have a friend with same car. I think I got a body computer I can send you if you want. Forget which one. Find the part number you need and I will check if its the right one. You pay postage and its yours
Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
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From: Arizona
Thankyou man I appreciate it. I'll see if I can get that computer and do the swap. It's So Random this morning here in Arizona it has for the most part been fine. Sucks hah let you know when I do it. O and the ecm is on the passenger floor right? I think I read that somewhere.
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Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
Likes: 0
From: Arizona
Hey sam I never realized that, that's the ecm! No wonder why I have problems! The freaken last owner never had a cover for it and I never knew what it was and I wanted to get one but finding one used has been a p.i.t.a. I wonder if it's just dusty in there. Hope fully no water damage uh 😞 clean it up with electrical cleaner. I also noticed that when the problem starts happening if I just turn off the car and restart it, it works fine again. Definitely going to make a cover or get on asap! Really hope it's just dirty contact or something.
Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
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From: Arizona
Took apart the ecm today all looks ok cleaned it up a little hopefully helps. Been reading on here about capacitors that go bad, cause all kinds of problems and can ruin the board think this might be the issue. 17 year old capacitors just may be the culprit.
Thread Starter
Driver School Candidate
Joined: Aug 2016
Posts: 17
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From: Arizona
Yea I'll have to ask but on one of the posts it says it the 2jz has this issue also. https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/715345-how-to-check-your-ecu-without-removing-it-from-car-by-yamae.html
I'll have to try this
I'll have to try this