8640 electronic module

bison · Jun 13, 2016

I am looking for an electronic module that operates the warning lights and gauges on a 8640.
Dealer tells me that part is no longer available separate,..one has to buy the whole gauge cluster assembly,...$1750.
:shock:

thanks

Tx Jim · Jun 13, 2016

Is the module you're referring to parts key 12? Have you attempted to get module repaired?

bison · Jun 13, 2016

The part # 12 you referred to is the chip board,..I believe the module is at the very bottom of the breakdown pic.
Either one or both could be defective.
Dealer says there is no fix or test for these,..if failure is suspected replace module and/or chip board.

Problem i am having is that none of the warning lights come on when the key is turned on. Power to the cluster is OK and so is ground.

Tx Jim · Jun 13, 2016

There's nothing else lower in photo than parts key 12 except the screw(parts key 1). Did you check wiring harness ground connections?

tim s · Jun 13, 2016

I have had good luck with Ag-Express electronics in Sulphur Springs In. 765-533-4809,,give them a call and explain your issue,, they may be able to repair and test it for you I get the 55/60 series circuit boards repaired there they cost $1100 from Deere ,,get them repaired for $175

bison · Jun 13, 2016

(quoted from post at 14:26:40 06/13/16)
There's nothing else lower in photo than parts key 12 except the screw(parts key 1). Did you check wiring harness ground connections?

e bad, no 12 is the module.
No 17 is the circuit board.

bison · Jun 14, 2016

Yes, all harness and dash/cluster ground connections are verified good.
My repair manual tells me to replace module

bison · Jun 14, 2016

(quoted from post at 15:40:16 06/13/16) I have had good luck with Ag-Express electronics in Sulphur Springs In. 765-533-4809,,give them a call and explain your issue,, they may be able to repair and test it for you I get the 55/60 series circuit boards repaired there they cost $1100 from Deere ,,get them repaired for $175

Will do.
Thanks.

Tx Jim · Jun 14, 2016

This what shows up w hen part number(AR90145()for parts key 12 is entered.

RE66827 Tachometer Reman - TACHOMETER (IAWS REMANUFACTURED) 1,074.76 USD which BTW is parts key 18

bison · Jun 14, 2016

(quoted from post at 03:32:00 06/14/16)
This what shows up w hen part number(AR90145()for parts key 12 is entered.

RE66827 Tachometer Reman - TACHOMETER (IAWS REMANUFACTURED) 1,074.76 USD which BTW is parts key 18

hey don't exactly give it away either :shock:

8640 electronic module

bison

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Tx Jim

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bison

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Tx Jim

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tim s

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bison

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