Hi All,

I've been able to get my coolant gauge to work reasonably well by using the EMS's user #1 pulse width modulator. Every EMS is different so these settings may not work with your setup without some tweaking. This is not a flawless solution as I'm trying to drive something that is frequency modulated using a pulse width modulated controller so it is in no way a better solution than Modifry's box! This solution is not very configurable, possibly innaccurate at times but requires no hardware and possibly even no wiring changes.

The ECT gauge is connected to pin A1 (PW2 out) (All pin locations will be given in the order specified in the AEM EMS pin out document for the 1012 ecu). Most of us boosted folks have this connected to the boost control solenoid and if this the case you should connect this wire a Low Side driver, such as LS9 (pin A22). I am using LS9 in these examples, but if you are not using an AEM driven boost controller then it may work if you just change all references of LS9 to PW2 without any need to do any rewiring.

I have two setups here. The first will light 3 bars when up to optimal temperature, the second will light up two bar when optimal. Both should increase the numbers of bars lit as temperature rises.

FYI - some of the pics appear to be coming in huge ... I have no idea why.

3 bars setup:






2 Bars setup:






To identify at approximately what temperatures the gauge will change you need to specify using three values.... 0 the gauge is off, 100 (represented as 99.61) the gauge is on all the bars, including the red on and the other number which is when the gauge is at either 2 bars with the 2 bar settings or 3 bars with the 3 bar settings.




Notes:
All of these settings are set to come on at lower temperatures than they normally would so you can test if this works for you.

The stock gauge updates pretty slowly to changes - that is normal.

Sometime the gauge will go from four or five bars to just 1 bar. This should be considered as high temperature. There is a 'gap' where the pulse width gets too small and if the gauge detects this it goes in 1 bar mode.

The 3 bars approach may work better than the two bars approach.

There isn't a great degree of control on when the bars change. Just move the values around in the pulse widths table. Values other than those in the tables won't work!

This will only work correctly when the car is running (internal EMS voltage issues)

If no bars appear then the User #1 table value needs to be increased a tiny bit

if 3 bars appear when you expect 2 bar (because you are using the 2 bar configuration) then the User #1 Period in the options needs to be increased a tiny bit.

Let me know how this goes

 

Sounds like a job for MODIFRY! Its a bird! Its a plane! Its MODIFRY!

John

 

Modifry's box is great These details are only for those who really know the EMS and this doesn't work as well as Modifry's box either.

 

Nice job, Giles. I hope others will appreciate the fact that you've shared this with the boards.

Best,
CB

 

Thanks Chris! I finally got around to taking a look at this and got it to work 'ok' in no time.

The following table will give you 'like stock' performance of the gauge with the 3 bars option settings:



For those with cooling mods you might want to stick with the original settings as the bar will start to rise much earlier.

 

great work Gilbert!

I've been tinkering with the PW2 settings to convert it to a shift light (all bar at 8900rpm) or a knock voltage meter. I've not had too much time with this so it has not been as successful as your work. Do you have any tips?

I did not know that you can use this for ECT. I will give this a try. Thanks.

 

The coolant temperature gauge responds too slowly for something like that, or are you trying to drive something else? I'm sure we could get your check engine light to flash at different rates as the rpm rises, etc...

 

^ I think that is the problem. I used the stock coolant gauge and found that it's not quick enough . Thanks Gilbert.

I wired an autometer shift light to the HS output and found that its a tad slow as well but not as slow as the ect gauge. It's still useable though. I think it's best to use LED for shift light.

 

You may well already be using the check engine light (LS10) for something but if you are then you can use the immobiliser light instead (Injector 9)

 

That's a good idea. The autometer light for warning and imobiliser light for shift.

Gilbet, is Injector 9 the same as Fuel 9?