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I hooked up the multimeter to the negative terminal to test parasitic draw and getting 1.5A draw. I've pulled every fuse in the trunk, driver side panel and also under hood driver side, yet the draw is still exactly at 1.5A. To be clear, I've only pulled fuses, none of the relays and such.
However, I'm beginning to think this is a SAM issue because there are other issues such as 1) ac doesnt work 2) some tail lights are out 3) battery drain 4) srs light
What's the best way to tell if it for sure is SAM module and how to find out WHICH SAM module (trunk or front etc)?
Each SAM is fed with power from the front Pre-fuse box near the battery. You can measure current draw through each fuse there to start identifing where the source is.
However pulling fuses is a bad strategy looking for parasitic drain.!
If you pull a fuse, then that may be enough to stop some component from going to sleep. Also it can take 10 to 20 mins from LOCKING the car for all systems to fully sleep!
What you need to do is test with the fuse fitted, and after locking the car and waiting. There are amp testers designed for this for a few £/$ online that plug into the fuse space and replace the fuse. Make sure you get the right one!
I hooked up the multimeter to the negative terminal to test parasitic draw and getting 1.5A draw. I've pulled every fuse in the trunk, driver side panel and also under hood driver side, yet the draw is still exactly at 1.5A. To be clear, I've only pulled fuses, none of the relays and such.
However, I'm beginning to think this is a SAM issue because there are other issues such as 1) ac doesnt work 2) some tail lights are out 3) battery drain 4) srs light
What's the best way to tell if it for sure is SAM module and how to find out WHICH SAM module (trunk or front etc)?
Hi,
Before you try anything else, first check your alternator. İt might show that it is putting out enough charging amperage but it might be drawing current as well. This happens due to faulty rectifier or diode tray. The purpose of diode tray is that it acts as one-way gateway for the power and also how much power is being produced. İt acts in conjunction with the voltage regulator. İt is a very simple process and can be done with the help of a multimeter.
Hi,
Before you try anything else, first check your alternator. İt might show that it is putting out enough charging amperage but it might be drawing current as well. This happens due to faulty rectifier or diode tray. The purpose of diode tray is that it acts as one-way gateway for the power and also how much power is being produced. İt acts in conjunction with the voltage regulator. İt is a very simple process and can be done with the help of a multimeter.
I measured with a multimeter at charging and it looks fine but you're saying that's not enough? How do I check for this faulty rectifier or diode tray?
Each SAM is fed with power from the front Pre-fuse box near the battery. You can measure current draw through each fuse there to start identifing where the source is.
However pulling fuses is a bad strategy looking for parasitic drain.!
If you pull a fuse, then that may be enough to stop some component from going to sleep. Also it can take 10 to 20 mins from LOCKING the car for all systems to fully sleep!
What you need to do is test with the fuse fitted, and after locking the car and waiting. There are amp testers designed for this for a few £/$ online that plug into the fuse space and replace the fuse. Make sure you get the right one!
Thank you for that advice! I'm going to get this device to try out, but I'm a bit unclear what to do with it, I'll look up the youtube. However, the diagram you attached, is there a specific fuse slot I should be using this with for the clk?
Last edited by bumpersignal; Sep 1, 2025 at 04:33 PM.
I measured with a multimeter at charging and it looks fine but you're saying that's not enough? How do I check for this faulty rectifier or diode tray?
There are many YT videos on how to test an alternator, and they explain the procedure much more comprehensively than anyone (well, at least me) can do here.
Each SAM is fed with power from the front Pre-fuse box near the battery. You can measure current draw through each fuse there to start identifing where the source is.
However pulling fuses is a bad strategy looking for parasitic drain.!
If you pull a fuse, then that may be enough to stop some component from going to sleep. Also it can take 10 to 20 mins from LOCKING the car for all systems to fully sleep!
What you need to do is test with the fuse fitted, and after locking the car and waiting. There are amp testers designed for this for a few £/$ online that plug into the fuse space and replace the fuse. Make sure you get the right one!
Sorry, please ignore my previous question. I re-read your post and it all makes sense now. Thanks!
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