$EE Code for electric water pump on AIR output

[dzidaV8]

OK, so the subroutine would look like this:

;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
;
; Routine to enable Electric Water Pump when engine not running
;
;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9000    1D 00 01            bclr    0, X, #%00000001       ; Disable WP (X already set to $1800)
9003    B6 01 28            ldaA    L0128                  ; Load A/D Ignition Voltage
9006    81 30               cmpA    #$30                   ; Compare to 48
9008    23 0A               bls    @1                      ; Bra to return if Ign Voltage <= 4.8V (Ignition off)
900A    B6 01 92            ldaA    l_0192_CoolTmp_fltrd_$f0    ; Load Coolant Temp
900D    81 B9               cmpA    #$B9                   ; Compare temp to 99 deg C
900F    23 03               bls    @1                      ; Bra to return if Temp <= threshold
9011    1C 00 01            bset    0, X, #%00000001       ; Enable WP (X already set to $1800)
9014    7E 49 44        @1  jmp     L4944
;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

And:

4935    CE 18 00            ldX    #$1800
4938    12 23 80 05         brset   L0023, #%10000000, @7
493C    7E 90 00            jmp     L9000 ; jump to new subroutine
493F    20 03               jr    @8
;
4941    1C 00 01        @7  bset    0, X, #%00000001

Now I just need 23 bytes of program memory to add my subroutine. Kur4o, can you point me at some usable address?

[EDIT] I've found E-side 0x9000 - 0x93FF marked as free memory in EEXtra.xdf, so I guess the subroutine goes to 0x9000 :)

[kur4o]

Half the bin is empty.
You can start at the lower section to keep all patches nice and tide.
I suggest to use F000-FF00 memory range.

also use subroutine bd code.

at 4935 put
BD F0 00 20 0A

at F0 00 write your subroutine and add the return instruction [39] at the end

[steveo]

just curious, why do you want ECM control of the electric waterpump?

and if so, why not just use the fuel pump relay to trigger a second relay if you only want it on when the engine is running? (although you'd get a prime cycle, that shouldn't be a big deal...)

it's a cool project, just curious

[dzidaV8]

just curious, why do you want ECM control of the electric waterpump?

and if so, why not just use the fuel pump relay to trigger a second relay if you only want it on when the engine is running? (although you'd get a prime cycle, that shouldn't be a big deal...)

it's a cool project, just curious

Because... why not? :)

A feature to have the pump work on hot engine while it is off might get useful sometime.

[lionelhutz]

Did you ever consider PWM control and remove the thermostat? By remove, I mean disable it in the full open position or modify the pump to do the equivalent.

Then, you'd cool more than just down to the thermostat closing temperature by running the pump with the engine off.

[dzidaV8]

Did you ever consider PWM control and remove the thermostat? By remove, I mean disable it in the full open position or modify the pump to do the equivalent.

Then, you'd cool more than just down to the thermostat closing temperature by running the pump with the engine off.

I didn't think about it. Removing the thermostat is not a good idea, as the heat-up using the main circulation (through the radiator) would take much longer. The heater would also be less effective without it.
The PWM control might be useful to shorten the warm-up time, and maybe to free up a fraction of horsepower lowering PWM at WOT momentarily, but not much more. The pump in the car I'm working on consumes only around 7 amps, so almost nothing for the alternator.

The modern cars have thermostats with electric heater integrated in the viscous fluid to vary the opening and closing temperatures some. Anyway, why would you want to cool the car to temperatures lower than thermostat temp?

[lionelhutz]

The idea is that the PWM runs the pump slow during warm up. Decently implemented, a PWM pump and PWM fan will maintain a fairly constant engine temperature. Some OEM's are doing PWM instead of letting the thermostat regulate the engine temps. They probably build the system to have flow to the heater core first though using some other method.

You don't want to keep cooling your engine to thermostat temperature or even below it when it's OFF?