1987 944 speedometer circuit resistor value

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Teapurist12
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Hello all ,
My 944 has been without a speedo since I bought the car , I have just disassembled the speedometer gauge and discovered that one of the resistors has burned out on the small PCB on the rear of the gauge (as shown in pictures) .
I have attempted to clean it up to read the value of it but to no avail would any of you happen to remember this value off the top of your heads , for reference it is a 1987 944 Lux( base ) RHD with MPH speedo .
thanks , James
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1987 944 lux 2.5 8v
1977 land rover series 3 LWB 2.25 petrol
1954 MG TF midget 1250
2002 Volvo v70 2.4 manual

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whalenlg
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33 ohms according to this schematic and datasheet.

Same thing happened on mine due to a shorted capacitor, so replace both large caps that connect to the resistor.
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1986 951 - Silicon Valley

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Teapurist12
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whalenlg wrote: Sun Dec 01, 2024 6:35 am 33 ohms according to this schematic and datasheet.

Same thing happened on mine due to a shorted capacitor, so replace both large caps that connect to the resistor.
Excellent thanks , is it worth replacing the IC chip while in there or re they usually Ok

Thanks , james
1987 944 lux 2.5 8v
1977 land rover series 3 LWB 2.25 petrol
1954 MG TF midget 1250
2002 Volvo v70 2.4 manual

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whalenlg
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I didn’t need to replace the chip. Might be very hard to even find one. Very unlikely that the capacitor failure would take out the chip.
1986 951 - Silicon Valley

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Teapurist12
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sure enough the 100uf capacitor had failed which I would figure took out the resistor
1987 944 lux 2.5 8v
1977 land rover series 3 LWB 2.25 petrol
1954 MG TF midget 1250
2002 Volvo v70 2.4 manual

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Teapurist12
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whalenlg wrote: Sun Dec 01, 2024 9:46 am I didn’t need to replace the chip. Might be very hard to even find one. Very unlikely that the capacitor failure would take out the chip.
on the topic of the IC chip , it seems to be ok ,just waiting on a odometer gear to rebuild the dash cluster , you can still order them from ebay (here in the UK anyway ,link attached ) coming straight on the slow boat from china though . always good to know just in case
https://www.ebay.co.uk/itm/192623621120 ... 59.m146925

James
1987 944 lux 2.5 8v
1977 land rover series 3 LWB 2.25 petrol
1954 MG TF midget 1250
2002 Volvo v70 2.4 manual

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