ECM Failure?

1075tech

1075tech

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Can an ECM progressively fail?

2003 Mitsubishi Eclipse Spyder GS with 2.4l. 123k. miles.

First, the radio stopped working. Clock works. Displays stations. No sound.

Then, the factory anti theft alarm would go off every time you opened the door. We were able to disable this by unplugging the door, trunk and hood switches.

Then there was a problem starting the car. Diagnosis was a bad starter and it was replaced.

Now there's no speedometer or odometer function. Tach works fine. Rest of the car works ok for it's age.

I hate electrical gremlins.
 
I think the first module I had in a car that failed was a 1976 Mercury Capri. It would turn on and off like a light switch.
 
I'm no good on vehicle electronics. Wire your house? Sure. Wire for a car stereo? Nope.

It's my son's car. He's getting frustrated with it but really isn't in a position to replace it. He got it for $1500 and we've put $700 into it.

Water pump, thermostat, 2 tires, and the starter.

Runs great. Doesn't burn or leak oil. Gets good gas mileage - 24/29. And it's a convertible.

I'm just trying to help him where I can
 
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My last bike has an engine control module, and a body control module, with a CanBus system.

I am completely out of my depth. If it ain’t in the factory service manual, I got nothing.
 
1075tech said:
Can an ECM progressively fail?

2003 Mitsubishi Eclipse Spyder GS with 2.4l. 123k. miles.

First, the radio stopped working. Clock works. Displays stations. No sound.

Then, the factory anti theft alarm would go off every time you opened the door. We were able to disable this by unplugging the door, trunk and hood switches.

Then there was a problem starting the car. Diagnosis was a bad starter and it was replaced.

Now there's no speedometer or odometer function. Tach works fine. Rest of the car works ok for it's age.

I hate electrical gremlins.
Click to expand...
Yes, and I would check the grounds at the controllers. Also what is the AC voltage at the alternator. I've had several good alternators that were screwing with the controllers because the AC voltage reading was out of whack but the DC reading was correct.
 
fieldgrade said:
My last bike has an engine control module, and a body control module, with a CanBus system.

I am completely out of my depth. If it ain’t in the factory service manual, I got nothing.
Click to expand...
I guess maybe BCM vs ECM?

Engine runs great. So maybe the body control module?
 
heavydoc said:
Yes, and I would check the grounds at the controllers. Also what is the AC voltage at the alternator. I've had several good alternators that were screwing with the controllers because the AC voltage reading was out of whack but the DC reading was correct.
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I'll have him get that checked. What should the AC voltage be?
 
It is very low, I'll look it up for a 12 vdc system in the morning, maybe tonight if I finish cooking soon
 
Just googled this, I think 50mv is still kinda high1000003588.jpg
 
1075tech said:
I'll have him get that checked. What should the AC voltage be?
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Depends on the load on the alternator. The higher the load, the higher the ripple. Normally you'll read under .1VAC with a multimeter. You won't have to worry about splitting hairs over the reading though. When AC leakage is high enough to cause problems it'll be really high. Over a volt.
Joe
 
Plug a code reader into the OBD II port
Not just a simple emissions reader but something like a Snap-on Solus that can read/operate everything on the vehicle
 
Id look for a forum specific to the vehicle because...

You might be able to fix the issue with a soldering iron. Since the morons in charge dont allow lead solder anymore, the old solder (which is often inadequate from the factory) needs to be reflowed and/or added to

Had to do this to a board on the crx, and should do it the stupid electronic speedo on the civic
 
Have you checked the relays? Sounds like it could be a box full of old bad relays. If the car still runs fine I would highly doubt the ECM esp with that lower mileage.

Pull them and see if they look toasty. Then go to napa and get some good replacements.
 
I agree with @heavydoc progressive seemingly unrelated electronic failures in a car that old, something in common, bad ground connection, or an issue with the power getting to them, I lean ground first.
Now everything you mentioned is likely BCM stuff, so maybe, if the car has one. Common reasons they fail, vibration, bad power, or high load - frequently a bad ground, or poor factory solder.
 
Clean the battery terminals and clamps, they may look clean but often are not. I like the black battery washers at walmart auto dept. $1.
 
Also if you need parts. Check the Local Junkyard/LKQ for parts

See if any of the Fuses are Burnt but because how low the prices is. Might as well keep driving it until the wheel comes off but definitely get Speedometer Working
 
There is a ground in the left kick panel for the front ECU. also a ground for the BCM behind the junction block. Could be either one loose or corroded.
 
Yes, the ECM can progressively fail -
I have a 2006 Dodge Dakota and there's a few years that the TCM/PCM does progressively fail - and the Dodges share the same module with the Mitsubishi Raider.
Mine started out with intermittent transmission overheat warning light coming on, and at it's worst the transmission wouldn't hit the shift points or even be able to use any gear except 2nd and 3rd.
I ended up getting a replacement from some janky place up in NY/NJ who forgot to program it with the right VIN the first time.
Currently, it's working well enough but I kept the old module so I can find someone different who might could fix it.
Google your son's car model and the Raider to see what parts they share, hopefully not the ECM/TCM/PCM (transmission control module/powertrain control module).
ETA - I went with the janky place because very few people repair these any more.
 
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Oneofsix said:
Yes, the ECM can progressively fail -
I have a 2006 Dodge Dakota and there's a few years that the TCM/PCM does progressively fail - and the Dodges share the same module with the Mitsubishi Raider.
Mine started out with intermittent transmission overheat warning light coming on, and at it's worst the transmission wouldn't hit the shift points or even be able to use any gear except 2nd and 3rd.
I ended up getting a replacement from some janky place up in NY/NJ who forgot to program it with the right VIN the first time.
Currently, it's working well enough but I kept the old module so I can find someone different who might could fix it.
Google your son's car model and the Raider to see what parts they share, hopefully not the ECM/TCM/PCM (transmission control module/powertrain control module).
ETA - I went with the janky place because very few people repair these any more.
Click to expand...

Circuitboardmedics.com maybe?
 
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