old_man
NAXJA Forum User
- Location
- Loveland, Colorado
Like it says, does anybody know the current draw of a Renix ECU? I am doing a project and need to know.
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Anybody measured the current draw of a Renix ECU?
- Thread starter old_man
- Start date
Runnin'OnEmpty
NAXJA Forum User
- Location
- Southeast USA
A few years ago I measured the draw on an 89.
The best I remember it was 8ma. This was with the
key off; never tried it with the key on.
This is about twice what modern PCMs pull, at least
on Fords. There's a standard that mfgs have to use,
and the current draw is supposed to be low enough
so that the vehicle can be started after at least 30
days of sitting...
The best I remember it was 8ma. This was with the
key off; never tried it with the key on.
This is about twice what modern PCMs pull, at least
on Fords. There's a standard that mfgs have to use,
and the current draw is supposed to be low enough
so that the vehicle can be started after at least 30
days of sitting...
old_man
NAXJA Forum User
- Location
- Loveland, Colorado
I am looking for the draw when running. I have seen a couple of rigs with the same problem I am seeing. They won't start whent he battery is low but they still crank fine. This is especially true when they have upgraded battery cables, allowing less cable losses, and will crank on lower voltages.
I am building a SEPIC converter that will regulate the voltage to the ECU, even boost it to 12V if it is as low as 4 volts or regulate it down if the voltage is too high. I have seen that when the cranking voltage goes down to around 7 volts or below, the ECU quits triggering a spark, even though you might be cranking the motor fine. By doing this, you have a fighting chance of having it start even on a very cold morning and an old battery.
I was just wondering if anybody had measured the current draw. If not I will measure it this weekend.
I am building a SEPIC converter that will regulate the voltage to the ECU, even boost it to 12V if it is as low as 4 volts or regulate it down if the voltage is too high. I have seen that when the cranking voltage goes down to around 7 volts or below, the ECU quits triggering a spark, even though you might be cranking the motor fine. By doing this, you have a fighting chance of having it start even on a very cold morning and an old battery.
I was just wondering if anybody had measured the current draw. If not I will measure it this weekend.
8Mud
NAXJA Forum User
- Location
- Central Germany
I'd also take a look at the larger yellow wire going to the ignition module and maybe figure that into your boosted (regulated) power source. Or add a relay and have the yellow wire activate it and pick up main power at the starter relay red wire lug.
I've had the engine bay packed with mud and water and had a no start, on numerous occasions. Part of it was excessive cranking (battery down a bit), part of the problem was line loss (poor design). A whole bunch of it was little electrical leaks (through water and mud) added up to a big problem.
I didn't research it all that well, but came to the conclusion you are likely to get enough spark for a start with 9 volts, unlikely to get enough spark for a start with 6 volts going to the ignition module. Seems to be a lot of line loss in this circuit anyway, the coil is low resistance and helps to suck down the voltage, add some water,mud, a low battery and you may not get much if any spark.
I've had the engine bay packed with mud and water and had a no start, on numerous occasions. Part of it was excessive cranking (battery down a bit), part of the problem was line loss (poor design). A whole bunch of it was little electrical leaks (through water and mud) added up to a big problem.
I didn't research it all that well, but came to the conclusion you are likely to get enough spark for a start with 9 volts, unlikely to get enough spark for a start with 6 volts going to the ignition module. Seems to be a lot of line loss in this circuit anyway, the coil is low resistance and helps to suck down the voltage, add some water,mud, a low battery and you may not get much if any spark.
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