just checking... your ac light is lit when it is on ...
this differs from pre facelift where ac light is off when ac is on.
this differs from pre facelift where ac light is off when ac is on.
The elusive AC and Front SAM issue
Good day, I did the capacitor replacement repair but it only worked for a month. There must be something else in the SAM contributing to this problem…
Usually I’d turn the fan speed dial to 0 to turn it off but I started to fiddle with the A/C button on and off this week. Maybe that has helped to cause the problem idk.
Based on what I’ve read here, my front SAM should not even have been affected by the issue since it has the most recent part #.
Any ideas?
Usually I’d turn the fan speed dial to 0 to turn it off but I started to fiddle with the A/C button on and off this week. Maybe that has helped to cause the problem idk.
Based on what I’ve read here, my front SAM should not even have been affected by the issue since it has the most recent part #.
Any ideas?
1 - 20 of 48 Posts
Yes, AC light is lit when AC is on.
The car responds when I toggle it on/off but ac compressor no longer comes in
The car responds when I toggle it on/off but ac compressor no longer comes in
If you can take a voltage reading at the compressor that will confirm a lot. Back probe both of the two wires at the electrical connector at the compressor with the engine running and the cooling set to max. If you have voltage (may be less than 12 volts) at one of the two wires (the other will be the ground) that confirms that you are getting the current to the compressor so there is nothing wrong through the SAM or any other part of the electrical system. And it means the compressor has failed - time to replace it. If you don't have voltage then you need to figure out where you are losing it.Good day, I did the capacitor replacement repair but it only worked for a month. There must be something else in the SAM contributing to this problem…
Usually I’d turn the fan speed dial to 0 to turn it off but I started to fiddle with the A/C button on and off this week. Maybe that has helped to cause the problem idk.
Based on what I’ve read here, my front SAM should not even have been affected by the issue since it has the most recent part #.
Any ideas?
Silly question, but are you saying Light on=A/C off? Which is at odds with the manual which states: "The indicator lamp in the A/C button lights up. The cooling system is activated"?just checking... your ac light is lit when it is on ...this differs from pre facelift where ac light is off when ac is on.
Silly question, but are you saying Light on=A/C off? Which is at odds with the manual which states: "The indicator lamp in the A/C button lights up. The cooling system is activated"?
I could be wrong
edit: from your manual... u r correct
The indicator lamp on the air condition
on/off switch ° comes on.
we have had later prefacelift to include myself (2005 was mine) where ac light is out when ac is on
dang..2005 manual proves me wrong again!
The indicator lamp on the air condition
on/off switch ° comes on.
but i and others who had pfl state light is off when on
I quit ... Going to my happy place now
Hmm...worth me checking nevertheless.
Thx
Thx
Thanks for your replies guys. Please stay with me through this.
Now when I unplug the 2-pin connector that goes from the SAM to the compressor and give the purple wire 12 volts the compressor starts to work immediately and the car cools.
Interestingly, my SAM has the latest part # (16) which folks on here say should not have the dreaded capacitor issues like earlier non FL models.
Now when I unplug the 2-pin connector that goes from the SAM to the compressor and give the purple wire 12 volts the compressor starts to work immediately and the car cools.
Interestingly, my SAM has the latest part # (16) which folks on here say should not have the dreaded capacitor issues like earlier non FL models.
The SAM is the last component in the chain of control that activates the compressor. As said,often,but not always, it is the culprit when the compressor is not activated. But as you already said,usually in older (pre-FL) models.Thanks for your replies guys. Please stay with me through this.
Now when I unplug the 2-pin connector that goes from the SAM to the compressor and give the purple wire 12 volts the compressor starts to work immediately and the car cools.
Interestingly, my SAM has the latest part # (16) which folks on here say should not have the dreaded capacitor issues like earlier non FL models.
If I understand you correctly it started after you started fiddling with A/C on/off button? Maybe that button has gone bad? Mind you,just taking a guess here.
Below is an overview of the climate control system. Maybe it is of any help finding the culprit. Or have it read for faults by a competent mechanic.
Thank you for this!The SAM is the last component in the chain of control that activates the compressor. As said,often,but not always, it is the culprit when the compressor is not activated. But as you already said,usually in older (pre-FL) models.
If I understand you correctly it started after you started fiddling with A/C on/off button? Maybe that button has gone bad? Mind you,just taking a guess here.
Below is an overview of the climate control system. Maybe it is of any help finding the culprit. Or have it read for faults by a competent mechanic.
View attachment 628547
View attachment 628548
I will check right away!
The fact that the light goes on and off when I press the button tells me that the button itself is ok. Is that a good enough test?
I can also hear the blower fan slightly adjust speed with the pressing of said button.
Thanks Piet post 11 I knew I was not too wrong
Don't know,could also be a fault in the A/C controller itself. But,and I can not emphasize this strong enough, it is all guessing at the moment. Best thing you can do at this point is to take the car to a competent mechanic with SDS (MB's diagnosis system) and have it read for faults. Replacing parts at random will probably only drain your wallet.The fact that the light goes on and off when I press the button tells me that the button itself is ok. Is that a good enough test?
Ok
Going to get it scanned again.
The scan before the capacitor fix showed no communication to ac compressor.
i will update after
Going to get it scanned again.
The scan before the capacitor fix showed no communication to ac compressor.
i will update after
Okay,did not know you already had it scanned for errors.Ok
Going to get it scanned again.
The scan before the capacitor fix showed no communication to ac compressor.
i will update after
That indeed points to a problem with the SAM activating the compressor I think.
Maybe a bad wire going from SAM to compressor? Again,just guessing here.
No current coming from the SAM to the 2 wire compressor plug.
As cars have become more complex a specialist group have developed that are focused on deep diagnostic work. They use a host of bi-directional scanners, ocilloscope, and other advance testing tools. The starting point for them are complete understanding of electrical circuits and the abilty to fully read wiring diagrams. They confirm where a signal is supposed to begin and the path that it follows to the destination. That the source is providing the signal and it is arriving at its destination no matter how many other modules the signal goes through (see post #10 for an idea how many modules are involved). They do not guess where failure has occured, but rather fully confirms the diagnosis and the true fault.
The top repair facilities either have these specialist on staff or have access to them on an ad-hoc basis. The result is a 100% completed diagnosis. This eleminates the old effort to throw parts at a problem hoping one will fix the problem. That may have worked 30-40 years ago, but not today.
The top repair facilities either have these specialist on staff or have access to them on an ad-hoc basis. The result is a 100% completed diagnosis. This eleminates the old effort to throw parts at a problem hoping one will fix the problem. That may have worked 30-40 years ago, but not today.
If I remember correctly, the wire connection at the compressor (two wires) is acutally coming from the engine control module (ECM). I also seem to remember connector M18 on the top of the front SAM is a PWM for the compressor. Maybe that connection goes to and through the ECM.Okay,did not know you already had it scanned for errors.
That indeed points to a problem with the SAM activating the compressor I think.
Maybe a bad wire going from SAM to compressor? Again,just guessing here.
well said.As cars have become more complex a specialist group have developed that are focused on deep diagnostic work. They use a host of bi-directional scanners, ocilloscope, and other advance testing tools. The starting point for them are complete understanding of electrical circuits and the abilty to fully read wiring diagrams. They confirm where a signal is supposed to begin and the path that it follows to the destination. That the source is providing the signal and it is arriving at its destination no matter how many other modules the signal goes through (see post #10 for an idea how many modules are involved). They do not guess where failure has occured, but rather fully confirms the diagnosis and the true fault.
The top repair facilities either have these specialist on staff or have access to them on an ad-hoc basis. The result is a 100% completed diagnosis. This eleminates the old effort to throw parts at a problem hoping one will fix the problem. That may have worked 30-40 years ago, but not today.
But what about known issues?
1 - 20 of 48 Posts
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