“Cannot achieve constant peak widths” – Troubleshooting my Agilent 5973 MS

So my Agilent 5973 MS has been working like a gem, but I recently had to power it down. Recall from my previous blog, which I am sure you read, I had the power killed to my work bench. Although my system was working fine prior to the power down, I thought it would be good standard laboratory practice to tune my 5973 once I was back up running and pumped down. However upon doing so I was met with the following error:

Tue Oct 02 10:56:27 2012
App: msinsctl.exe, Method: VMS.M, RunType: Sampl, Vial: 1
DataFile: C:\MSDCHEM\1\DATA9281292812007.D
Macro: ADJ_MID_MASS, Cmd: widths 30,3
Cannot achieve constant peak widths.


If I read “Cannot achieve constant peak widths” one more time, I am going to burn my 5973 to the ground. To better understand my disdain for the aforementioned error, here is a list of some things I checked out, cleaned, replaced, tinkered with, etc…

  1. Vacuum was good and air/ water was spot on.
  2. The source was spotless.
  3. Filaments were virtually brand new.
  4. Brand new ETP had been installed.
  5. PFTBA was topped off.
  6. Etc…

I probably missed a few details, but you get the picture. I went up one side of this instrument and down the other. Nothing would work!!! The odd thing of it all was that the instrument would start the tune off looking great. 69, 219, 502 were there and looking purdy! However, as the tune went on and the system was “refining” itself, it would go from good to bad. It was as if my instrument was possessed to self-destruct every tune.

Cannot achieve constant peak widths… Cannot achieve constant peak widths… Cannot achieve constant peak widths… I think a fellow co-worker heard me murmuring my new mantra to myself.

I finally reached a point where I knew this was electrical/software related. The only physical component left to the MS, which I had not tinkered with, was the quad. I knew I had a new side board recently replaced, so that narrowed it down to software. Instead of reinstalling Chemstation, I decided to just do a new configuration on the instrument.

To do so, click on the “config” icon on our desktop (if yours is missing, you may also find it at: c:\msdchem\MSexe\msconfig.exe). From there, click on the drop down tab “configure” and select “instrument 1”. Now all you need to do is click “next” 6 times and then “finish”… and PRESTO!!! If you had a corrupt tune file as it appears I did, this will cure what ails you! In the end, it turns out I was just chasing my tail around, as this corrupt tune file was never going to allow for a proper tune.

15 Responses to ““Cannot achieve constant peak widths” – Troubleshooting my Agilent 5973 MS”

  1. JAG says:

    Grat tip,
    Same problem solved on a 5973N (6890N)

  2. archimonde says:

    Hey I have a similar problem. Last week, I turned off the because there was a scheduled power outage. Yesterday, I powered it back on. My tune ran fine but when i tried to perform a sample run, there was no baseline. I would be really grateful if you could help me out. Thanks

  3. Revathi says:

    OMG….thank you so much for this info..i just had agilent engineer service the instrument. And everything is tip top, and same as in your case the power cut in the building made to restart the instrument and when i did the tuning today it kept popping cannot achieve constant peak width. i guessed that the tuning values had something wrong..but didnt know how to solve. Thank u very much

  4. hana says:

    Thank you so much! It does solved my problem. I’m also using Agilent 5973 MS. I was reluctant to reconfigure it at first because my friend who has more experience with the instrument said it has nothing to do with the configuration. But it worked!! Thanks again ^^

  5. Mariela Rodriguez says:

    Thanks a lot, it was a great advice. It fix my problem as well.

  6. Michelle Yang says:

    Your commentary is EPIC and your information ROCKS! We had a power outage and out of all the instruments, only one (5973MS) decided to give us this error message. Followed your instructions and BOOM: TUNE COMPLETE. Thanks again for sharing your experience!

  7. Martin Kovac says:

    Thanks a lot, it fix my problem as well. GC MS Agilent 6850/MSD5973

  8. Ajit says:

    I have a similar problem. I am using 5975 MS with 7890 A GC. We had a power cut but only the computer turned off. After I started the system again and ran chemstation. I ran some samples but got no peaks. Before this system was working just fine. Then I tried autotune and same problem of `cannot achieve constant peak width ` appears. I tried the solution posted here but still the problem persists. I also tried to remove the existing tune files with the default version. and still no positive results. Any one.. plzz help..

  9. Kerri B says:

    THANK YOU! I didn’t have to press next 6 times but it worked just the same! I appreciate your post and your hilarious commentary.

  10. Pablo says:

    I read this possible solution here and there, I tried but same error appears…This is happening after turning off the GCMS for the summer period…Any thoughts?

  11. Chau says:

    It does not work for my 5975C (like some of you above have experienced)
    Please help!!!!
    Much appriciated!!!!

  12. Sean Flynn says:

    Worked on our 6890 GC/MS! Ran an autotune prior do doing some PM on the GC, went to run an autotune after the PM and initial values for 69 and so forth looks as to be expected, got halfway through the autotune and gave the aforementioned error message. Performed the reconfigure and poof, the MS was passing autotune’s again! Thanks!!!

  13. James Evans says:

    I have a similar issue where this procedure works temporarily as a bandaid.

    During Hurricane Harvey, we powered down everything. When we brought everything back up, my computer gave me the BSOD. So I had a new PC built and installed chemstation on it. Several weeks of perfectly fine tunes, I got hit with the “Cannot achieve constant peak widths” message. We found this page, tried it, it worked! Three weeks later, it happened again. Did this procedure again, and it worked! Three weeks later, it happened again.

    I went ahead and uninstalled chemstation and reinstalled. Hopefully that will cure what ails my instrument.

  14. Matthew Hoffman says:

    Thank you so much for publishing this!

    I was running a sample and all of a sudden we weren’t getting any response. In manual tune I would get a no emission current fault and in autotune it would start ok but then quickly devolve into nothing and give me the cannot achieve constant peak widths error.

    I put in new filaments and cleaned the source thoroughly and saw no improvement. I was about to start checking fuses and ohms but then I saw this and boom! Thank you!

  15. Laurent says:

    Dear Jason,

    Thank you verzy much for sharing your experience with this problem. We recently faced the exact same problem. I followed your protocol (reconfiguration of the MS) and it fixed the problem. That was very generous from you to share your solution with the community, many thanks for this.
    Best, Laurent

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