[TJay74]

I just wanted to share my experience in installing a JMS Fuelmax (voltage booster / boost-a-pump) on my 17 SS 1LE. I am guessing this process is the same or very similar for years of the SS 1LE.

The SS 1LE cars are put together a little different than the normal SS cars in the trunk area. On the SS cars the fuel pump control module is in the trunk (on the drivers side behind the side panel, it sits on a bracket on the wheel tub that also holds the RKE - keyless entry module).

On the SS 1LE cars the FPCM is under the car, it is located right above the drivers side stub axle right near the differential.

The instructions for the JMS need you to splice into the FPCM power wire, on the Camaro it is listed as a Red wire with a Purple tracer stripe on it. This is where this gets tricky.

If you remove the false floor, the plastic center section that covers the trunk latch and then move or remove the drivers side carpet covering you can access the wires from inside of the trunk.

- Start with disconnecting the negative battery cable.

-Once you get to where you can see the drivers side wheel tub in the trunk you will see a black bracket with 2 harnesses plug into it. Reference which plug goes where and unplug both of those plugs. Then remove the 2 - 10mm bolts and remove the bracket with the RKE module and set it aside.

-Under the RKE module bracket is the main wiring harness entrance into the trunk area. This is where you will be working. Carefully cut the cloth tape off of the harness near the wheel tub side and peel it back, you can cut it off and discard it as you will need to tape it back up where you are done.

-Once you have the covering peeled away you will find 3 Red wires with a Purple tracer on them in that harness. Here is where you may want to go under the car and pull the plug on the FPCM and drop the harness down so you can see the power wire. You want the Red wire with the thin Purple tracer stripe. You want the stripe that has a very defined edge on it, super crisp and sharp edges where the purple meets the red. The line is very thin when you compare it to the other 2 red/purple wires in that bundle. This is the wire that you will splice into with the JMS box.

-The white wire from the JMS box will splice into the wire that goes thru the rubber grommet and to the underside of the car, the red wire on the JMS box will splice into the other side of the wire that goes back towards the main harness.

Once you have spliced the wires make sure to tape the wires up separately and then tape the harness back up that you removed the cloth covering on. Then reverse your steps and put the RKE module back into place and move onto the setup part of the JMS box.

I have to give credit to Trevor (TMS) on this next part, his instructions are on point and will work. You will need a voltmeter of some sort in order to setup the JMS box correctly, another person will be helpful and you will need a way to monitor the throttle position (HP Tuners, Torque app or some other sort of configurable OBD2 app). Follow his below instructions and you will be on your way to getting the JMS Fuelmax set up and running.


-You need to calibrate both the input trigger and the output voltage on your car.

Below are my instructions on how to do this. Since you are using the accelerator pedal you need to configure the unit to ramp in using 0-5v sensor (accelerator pedal is the sensor) and not a time ramp. Thus switch #3 must be set to on. Further, you want to set switch #4 to on and #5 off so it configures the unit for a 0.4V increment which is the smallest increment. This will give the most granularity of the ramp in using the accelerator pedal. If this incremental voltage is set too high based on the dipswitch combinations of 4 and 5, then when the voltage starts ramping up it might go from 14.4v Base to 17.47V starting at 50% throttle and maxing out early at 60% throttle. We want to spread the ramp-in over the largest percentage of pedal movement possible (something like ramp in at 50% throttle and maxes out around 80% throttle).

Steps for configuration:

Note: it really helps to have a second person when it comes to setting the ramp-in trigger using the accelerator pedal.

1) You'll test voltage on the white wire of the JMS booster (I used a sharp voltmeter probe to pierce the wire insulation).

2) On the dip switches - 1 is on (program settings mode), 2 is off, 3 is on, 4 is on, 5 is off.

3) Output Voltage Set - Two ground wires coming out of the JMS Pedal harness near the accelerator (gray and black) get touched together with car running. Turn the dial knob on the JMS unit labeled "adjust output voltage" until you get as close to 17.47V as you can on the voltmeter. At this point, you have set the output max voltage. Turn dip switch 1 off to save the programming changes (before you kill power). Now, disconnect the two ground wires (gray & black) from each other and tape each of them up so they don't accidentally ground out. These stay unconnected. Shut ignition off.

4) Input voltage ramp-in trigger - This is where a 2nd person comes in handy. Turn the ignition on with engine off. Turn Dip switch 1 on to go into programming mode. With HPTuners VCMScanner connected (or whatever tuner you are using), monitor the "Accelerator Pedal Position" channel. Push accelerator pedal down until you reach as close to 50% on this channel (pedal should be about half way down). Now while one of you is holding the pedal steady at 50% have the second set of hands turn the "Adjust Input Trigger" dial on the JMS unit up or down until the base voltage of 14.4V begins to just start ramping up. Once that dial is set, test your ramp-in to make sure everything works properly. Simply let off of the accelerator pedal. Have your partner watch the voltmeter. It should stay steady at about 14.4V. then slowly press the pedal down until you get to 50%. 0%-50% throttle should stay at 14.4V. Once you go above 50%, the voltmeter should start registering an increase in voltage. Have your helper call out the voltage while you keep pressing the pedal down. Your partner should see the voltage climb up to and max out at 17.47v or so (whatever the max voltage ended up being on the previous step). It will likely max out somewhere between 75% and 80% throttle position which is perfect. Then, as one final test, just mash the pedal to the floor and make sure the voltage goes to 17.47v. Now make sure you turn dipswitch 1 off to save your settings (before you kill the ignition).

You're Done!

Hope this helps.

Trevor




I hope this helps everyone out. I can tell you after messing with this install over the last week now I am glad to be done with it. Now time to finalize my tune, throw it on a dyno and then find some sticky tires and go to the track and see what the car puts down for times.

Todd

[manders500]

Thanks for the great post Todd!