Senders for VDO 52mm temp guages - accuracy results from testing

Discussion in 'Electrical' started by A.N. Other, Apr 25, 2010.

  1. A.N. Other Banned after significant club disruption Dec 5th 2

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    I have been having issues with gauges under-reading on my track car, so yesterday, I hooked up the guages direct to the car battery (to eliminate any loom issues), and dropped the senders, wired up also, into a kettle, and boiled it.

    I have two VDO 52mm temp gauges which were used to do the tests with:

    1) 50 - 150 degrees C (for oil) - "150 gauge" - OEM Mk1 GTI
    2) 40-120 degrees C (for water) - "120 gauge" - bought new since non VW-supplied

    Here are my findings - every single sender I have was tested. There's no particular order - I dug them out, tested all. Some are marked identically & are grouped:

    Part no 150 gauge 120 gauge Sender volt Sender temp Other markings
    at boil at boil markings markings
    049 919 563 A 105 88 24V180ELTH Not stated 05-92
    049 919 563 A 107.5 88 24V180ELTH Not stated 05-92
    049 919 563 A 102.5 84 6-24V 150 degrees C 11-86 801/16/2
    049 919 563 A 105 87.5 6-24V 150 degrees C 3-86 801/16/2
    Zip all :-s 100 82.5 12V 125 degrees C none
    049 919 501 A 92.5 77.5 12V max 125 degrees C FKO DB
    049 919 501 93 79 12V 120 degrees C 11-81 804/6/2
    049 919 501 94 77.5 12V 120 degrees C 7 82 804/6/2
    027 919 501 98 80.5 12V 120 degrees C 5 93 804/6/6
    The only one that worked correctly is highlighted in red. This is now fitted to my oil temp gauge! There is no accurate reading for the 120 guage, with the best being 88 degrees! You can also see small variation between identical senders.

    The other markings are meaningless to me - dates I assume in column one though, but the others.... electronics gurus?

    Off the back of this, has anyone any suggestions as to what sender I should be using for my 120 degree guage?
     
    Last edited by a moderator: Dec 13, 2013
  2. EZ_Pete

    EZ_Pete Forum Junkie

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    Could it be that the water temp gauge is calibrated to deliberately under-read?

    People aren't very good at appreciating that engine coolant operates at higher than atmospheric pressure, and so doesn't boil at 100C. Intuitively, having your coolant temperature showing as 100C sounds too hot because of our familiarity with water boiling at this temperature at normal pressure. So they knock 10 or 20 degrees off the displayed temperature to make you feel better. :lol:

    No such perceptual worries about oil temp, because we don't visualise oil boiling?

    Is there any user-available calibration screw on the back of the gauge, at all?
     
  3. A.N. Other Banned after significant club disruption Dec 5th 2

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    I spoke to a VDO agent at they confirmed temps are actual temps so there is no offset for water pressure.

    Apparently the gauges/senders are reasonably accurate, but give or take a little.

    A 150 degrees sender suits a 150 degrees gauge
    A 120 degrees sender suits a 120 degrees gauge

    - all fairly predictable, yet not according to my testing results.

    I'm going to have the 120 gauge checked next.

    Some sender resistance data which may be useful to someone one day:

    Code:
    [B]40 - 120 degree gauge[/B]
    
    Temperature	  Resistance
    [COLOR="White"]......[/COLOR]	           ohms  
    						
    40	           287.4
    60	           134.0
    70	           95.2
    80	           69.0
    90	           51.2
    100	           38.5
    110	           29.4
    120	           22.7
    Code:
    [B]50 - 150 degree gauge[/B]
    
    Temperature	  Resistance
    [COLOR="White"]......[/COLOR]	           ohms  
    						
    50	           322.8
    65	           173.5
    80	           122.5
    100	           62.2
    110	           48.1
    120	           36.5
    130	           29.9
    140	           23.1
    150	           18.6
    
     
  4. rubjonny

    rubjonny Administrator Staff Member Admin

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    049 919 563 A - oil temperature gauge sender, 1 pin white, 0-180C:
    MK1/2 Golf MFA oil temp sensor, also used on MK1 type VDO oil temp gauge

    049 919 501 A and 027 919 501 are superceeded by 049 919 501 - temperature sender, 1 pin black, 0-125C:
    coolant temp gauge sender, MK1 Golf, MK2 2/3 Golf 16v

    1H0 919 563 - oil temperature sender, 0-150 C:
    MK3 Golf GTI oil temp sender for MFA

    049 919 563 B - oil temperature sender, 1 pin blue, 0-180C
    Audi VDO gauge temp sensor (not same rating as VW oil temp sender)

    From the haynes manual, resistance values for 049 919 501 A, 027 919 501 and 049 919 501:
    20C - approximately 1000 ohms
    60C - approximately 250 ohms
    100C - approximately 75 ohms
     
    Last edited: Apr 26, 2010
  5. Ben S

    Ben S Forum Junkie

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    is you kettle calibrated correctly? ;)
     
  6. A.N. Other Banned after significant club disruption Dec 5th 2

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    Cannot confirm!
     
  7. A.N. Other Banned after significant club disruption Dec 5th 2

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    Great -that makes sense of what's in the first 2 lines of the table in post 1: "24V180ELTH"

    :thumbup:

    I'll report back when I've had the 120 gauge tested. At the moment I've got an "049 919 563 A" sensor fitted to the water temp and have "red lined" the gauge at 88 degrees.

    Kinda rubbish and bodgy really!
     
  8. Mikey C Forum Member

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    Always been interested in how accurate these are, especially since there are so many slightly different senders and gauges around.

    Not sure if this will make a difference, depending on the cleverness of the electronics inside (probably not very) they may read differently if you have 12v or 14.5v supplying them - might be worth a try while you've got the kettle warm. Probably easiest to hook up a charger - they usually run at 14vish

    Have you corrected for your altitude too :lol:?
     
  9. Mook

    Mook Forum Member

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    :lol:

    Chris, this kind of stuff is great - really helpful :thumbup:
     
  10. altern8 Forum Junkie

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    good info
     

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