Help! I think my alternator died!!!
I've been following this thread. First off glad to hear its running. But....if this lady's observations are correct something has to be wrong. The flickering lights, burning smell, no start, suddenly starts, ect. Time will tell.
Also its great to see how helpful and patient some members are on here. I haven't commented because I didn't want to possibly stir any confusion, just let the couple people patiently helping her go at it. Good job guys and gals!
Also its great to see how helpful and patient some members are on here. I haven't commented because I didn't want to possibly stir any confusion, just let the couple people patiently helping her go at it. Good job guys and gals!
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Here is my favorite article on the Chrysler ignition system and how the ASD relates to it. http://www.motor.com/article.asp?article_ID=428
I tend to provide sources to my students and let them learn at their own pace. One of the biggest tools in a technicians box is the ability to locate information and use it.
Further the reason I told her to check for spark is that is the correct place to start when diagnosing a no start condition. I figured she didn't have a DRB to check it via the computer so I told her how to do it with what I figured she had. Since the ASD relay controls power to the coil and swapping it caused the jeep to start there are several possibilities. One the connection in the relay center was corroded and the swap cleaned the connections enough to make things work. Two the ASD relay is on the verge of failure but the jarring caused by swapping it caused the relay to start working.
There is also another interesting twist that may be involved. I like to call it the unrelated concern effect. The alternator may actually have been bad thus causing the initial symptoms. Then the ASD which was on the verge of failure conked out at the same time. This is one of the hardest issues for a technician to deal with as they tend to have tunnel vision and get hung up on the obvious problem in this case the burning smell and weird flickering lights right before the vehicle died. So it is no wonder that folks who may not be professional technicians would have issues with it.
I tend to provide sources to my students and let them learn at their own pace. One of the biggest tools in a technicians box is the ability to locate information and use it.
Further the reason I told her to check for spark is that is the correct place to start when diagnosing a no start condition. I figured she didn't have a DRB to check it via the computer so I told her how to do it with what I figured she had. Since the ASD relay controls power to the coil and swapping it caused the jeep to start there are several possibilities. One the connection in the relay center was corroded and the swap cleaned the connections enough to make things work. Two the ASD relay is on the verge of failure but the jarring caused by swapping it caused the relay to start working.
There is also another interesting twist that may be involved. I like to call it the unrelated concern effect. The alternator may actually have been bad thus causing the initial symptoms. Then the ASD which was on the verge of failure conked out at the same time. This is one of the hardest issues for a technician to deal with as they tend to have tunnel vision and get hung up on the obvious problem in this case the burning smell and weird flickering lights right before the vehicle died. So it is no wonder that folks who may not be professional technicians would have issues with it.
Thread Starter
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Joined: Apr 2012
Posts: 716
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From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
Hey, I'm still here fellas but I took a serious nap and now it's bedtime! I will be back on here tomorrow afternoon because I really would like to know the problem so it can be solved. Otherwise I have this nagging feeling, it will come back. There I go again with feelings- that's how I winded up changing the alternator.
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
Thread Starter
Senior Member
Joined: Apr 2012
Posts: 716
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From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
Every now and then I hear the engine rumble after start. It's weird. It's happened about 3 or 4 times and sounded rough like that when she started back up earlier.
Thread Starter
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Joined: Apr 2012
Posts: 716
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From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
Here is my favorite article on the Chrysler ignition system and how the ASD relates to it. http://www.motor.com/article.asp?article_ID=428 I tend to provide sources to my students and let them learn at their own pace. One of the biggest tools in a technicians box is the ability to locate information and use it. Further the reason I told her to check for spark is that is the correct place to start when diagnosing a no start condition. I figured she didn't have a DRB to check it via the computer so I told her how to do it with what I figured she had. Since the ASD relay controls power to the coil and swapping it caused the jeep to start there are several possibilities. One the connection in the relay center was corroded and the swap cleaned the connections enough to make things work. Two the ASD relay is on the verge of failure but the jarring caused by swapping it caused the relay to start working. There is also another interesting twist that may be involved. I like to call it the unrelated concern effect. The alternator may actually have been bad thus causing the initial symptoms. Then the ASD which was on the verge of failure conked out at the same time. This is one of the hardest issues for a technician to deal with as they tend to have tunnel vision and get hung up on the obvious problem in this case the burning smell and weird flickering lights right before the vehicle died. So it is no wonder that folks who may not be professional technicians would have issues with it.
Thread Starter
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Joined: Apr 2012
Posts: 716
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From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
IMPORTANT, PLEASE READ...
Read this from the article Autosurgeon posted. A few weeks ago Free helped me interpret code 12 that I came up with on a self- diagnostic-which states I need my 02 censor replaced..,
"Since the ASD Relay powers up numerous circuits, components that don't seem to be related to the ignition system can cause a no-start condition. On some systems, for example, the oxygen sensor heater elements are switched by the ASD Relay. So a shorted O2 sensor can lower the voltage available to the ignition system to the point where the engine won't start. Remember to check the available voltage at the coil(s) while the ASD Relay is activated and compare it to source voltage."
I have the sensor just haven't replaced it yet...
Read this from the article Autosurgeon posted. A few weeks ago Free helped me interpret code 12 that I came up with on a self- diagnostic-which states I need my 02 censor replaced..,
"Since the ASD Relay powers up numerous circuits, components that don't seem to be related to the ignition system can cause a no-start condition. On some systems, for example, the oxygen sensor heater elements are switched by the ASD Relay. So a shorted O2 sensor can lower the voltage available to the ignition system to the point where the engine won't start. Remember to check the available voltage at the coil(s) while the ASD Relay is activated and compare it to source voltage."
I have the sensor just haven't replaced it yet...
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
I've been following this thread. First off glad to hear its running. But....if this lady's observations are correct something has to be wrong. The flickering lights, burning smell, no start, suddenly starts, ect. Time will tell.
Also its great to see how helpful and patient some members are on here. I haven't commented because I didn't want to possibly stir any confusion, just let the couple people patiently helping her go at it. Good job guys and gals!
Also its great to see how helpful and patient some members are on here. I haven't commented because I didn't want to possibly stir any confusion, just let the couple people patiently helping her go at it. Good job guys and gals!

Hey, I'm still here fellas but I took a serious nap and now it's bedtime! I will be back on here tomorrow afternoon because I really would like to know the problem so it can be solved. Otherwise I have this nagging feeling, it will come back. There I go again with feelings- that's how I winded up changing the alternator.
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
IMPORTANT, PLEASE READ...
Read this from the article Autosurgeon posted. A few weeks ago Free helped me interpret code 12 that I came up with on a self- diagnostic-which states I need my 02 censor replaced..,
"Since the ASD Relay powers up numerous circuits, components that don't seem to be related to the ignition system can cause a no-start condition. On some systems, for example, the oxygen sensor heater elements are switched by the ASD Relay. So a shorted O2 sensor can lower the voltage available to the ignition system to the point where the engine won't start. Remember to check the available voltage at the coil(s) while the ASD Relay is activated and compare it to source voltage."
I have the sensor just haven't replaced it yet...
Read this from the article Autosurgeon posted. A few weeks ago Free helped me interpret code 12 that I came up with on a self- diagnostic-which states I need my 02 censor replaced..,
"Since the ASD Relay powers up numerous circuits, components that don't seem to be related to the ignition system can cause a no-start condition. On some systems, for example, the oxygen sensor heater elements are switched by the ASD Relay. So a shorted O2 sensor can lower the voltage available to the ignition system to the point where the engine won't start. Remember to check the available voltage at the coil(s) while the ASD Relay is activated and compare it to source voltage."
I have the sensor just haven't replaced it yet...
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Hey, I'm still here fellas but I took a serious nap and now it's bedtime! I will be back on here tomorrow afternoon because I really would like to know the problem so it can be solved. Otherwise I have this nagging feeling, it will come back. There I go again with feelings- that's how I winded up changing the alternator.
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
When she started back up, there was some squealing from the belt, do I need to tighten the tensioner a bit?
Thread Starter
Senior Member
Joined: Apr 2012
Posts: 716
Likes: 0
From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
Will leave it alone but do you remember you read the codes for me and the were 12, 21, 55? My last thread? Remember? Now, suddenly the code 21 is gone. Now it's only 12. When we saw the 21 you told me I needed an 02 sensor.
Check this out…now code 21 is gone. Poof! Into thin air! You sent me a link to get the o2 censor. I bought it on ebay. Now the code is gone. What do you think about that? What could have fixed it? Please tell me your thoughts about this.
Not trying to press the issue, I just can't help wondering... Good Morning!
Thread Starter
Senior Member
Joined: Apr 2012
Posts: 716
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From: Charlotte, NC
Year: 1994 Jeep Cherokee Sport
Originally Posted by freegdr
Yes replace o2 sensor codes were 12 21 55 disregard 12 and 55
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Yes I remember that 21s gone because you disconnected the battery. Thought you changed the sensor all ready. It may come back after driving some if its in the budget replace it.
Last edited by freegdr; Apr 12, 2014 at 05:53 AM.


