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Cat d series memory

AO299D

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Nov 14, 2019
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53
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Ontario
Is there like a CMOS battery in the machine ECM of a d-series skid steer every time high crank till battery dead it resets a few of the preventive maintenance timers and sometimes it says 8 volt DC low and don't even pick up the engine rpm. Seems u have to start it a few time then let it sit for 10 15 minutes then start it then everything works.
 

Nige

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Jun 22, 2011
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G..G..G..Granville.........!! Fetch your cloth.
The 8V DC is generated inside the ECM. It is the stabilized power used for things like the Throttle Position Sensor (amongst others).

There is no replaceable CMOS battery inside the ECM as there was many years ago in machines of a much older generation.

it might be a silly question but why do you have to run the battery down so far getting it to start in the first place.?
Do you know if the air intake heater is working.?
 

AO299D

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Nov 14, 2019
Messages
53
Location
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Yes I have to put a new battery on it but it would be interesting to know why it does that on just machines.
 

AO299D

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Nov 14, 2019
Messages
53
Location
Ontario
I guess I'm not sure but I can have it inside where it's relevantly warm and it only cranks for a couple seconds and it always starts fine when I have battery charged it's just after a few days sitting that it won't start.
 

Nige

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G..G..G..Granville.........!! Fetch your cloth.
This is the machine S/N DX200752 I assume..?
This is what the air intake heater should look like, #8 on the illustration below. First find it, then you have to figure out if it is working or not. We'll get to that later. Look for the electrical connection, circled in red.

The fact you say - "I can have it inside where it's relevantly warm and it only cranks for a couple seconds and it always starts fine" - leads me to believe the heater may not be working. it could be nothing more than a dodgy relay. Without looking up the heater logic I suspect it will be activated based on a signal from the coolant temperature sensor.

upload_2020-12-26_21-38-21.png
 

Nige

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Messages
29,856
Location
G..G..G..Granville.........!! Fetch your cloth.
Glow plugs or air intake heater, it still works the same way. The signal to pull in the coil for the glow plug relay comes from the ECM. So my bet is that it works from the coolant temperature. A question: - Does the coolant temp gauge on the dash indicate correctly.? If not it could be that the glow plug circuit is fine, it's just not getting the right signal when to fire off.

The resistance on each glow plug between the terminal on top and the body should be 0.95 ohms.

Simple way to check the glow plug relay #13A is to swap it for the start relay #13. They are the same Part Number. If the engine still starts then the relay is fine. See attachment.
 

Attachments

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