Factory Five GTM #102

Wiring Specification

Using ISQE Setup


Rev 0.0


Author: Bill Jenkins



Table Of Contents

Table Of Contents. 2

List Of Figures. 2

1      Terms. 3

2      Overview.. 3

3      Features. 3

4      Detailed Description. 3

4.1       Power Organization. 3

4.2       Master Controller 3

4.3       Power Controller 3

4.4       RF Controller 3

4.5       Radiator Fan Control 3

4.6       Power Distribution. 3

4.7       Wiper Control 3

4.8       Dash Wiring. 3

List Of Figures

Figure 1. Master Controller Block Diagram.. 3

Figure 2. Power Controller Block Diagram.. 3

Figure 3. RF Controller Block Diagram.. 3

Figure 4. Radiator Fan Control Circuitry. 3

Figure 5. Power Distribution Diagram.. 3



1         Terms




Accessory Power


Ignition Power


I-Squared Engineering


Master Controller


Power Controller


Peripheral Control Module (Engine Computer)


Radio Frequency



2         Overview

This document describes how the Factory Five GTM #102 is wired using the I-Squared Engineering 1+1 MOSFET system.  Minimal fuses are needed in this configuration, as the ISQE setup is FET based and handles all the switching and power control.  This setup also takes advantage of the RF Controller from ISQE for security and remote access.

3         Features

There are several key features that the car is wired for.  These are:


·         Keyless Entry

o       Shaved Door Handles

o       Door Solenoid to Lock/Unlock Door Controlled by Key Fob

o       Internal Door Handles Still work

o       Electronic and Mechanical Trunk Entry

·         True Keyless Start

o       Hidden Rocker Switch for ACC and IGN Power Enable/Disable

o       Push Button Start

·         Auto Dimming Mirror w/ Home Link and Map Lights

·         Interior Dome Light

·         Footbox Lighting

·         Cruise Control

·         AC/Heat

·         Power Windows

·         Power Side Mirrors

·         Radiator Fan Control

o       PCM Controlled

o       Low and High Speed Operation

·         Alarm System

o       Key Fob Arms/Disarms

o       Door and Trunk Sensors Detect Illegal Entry

o       Shock Sensor

o       Ignition Lockout

o       Ignition Lockout Override Button Combination for Emergency

·         In Dash Stereo w/ Navigation, Subwoofer, and Amplifier

4         Detailed Description

The ISQE solution uses several components to complete the system.  These consist of the Master, Power, and RF Controllers as well as the Ignition Lockout Module.  In short, the Master Controller handles the switching on/off of the desired functions, the Power Controller handles power delivery to the appropriate devices, the RF Controller handles the alarm and general key fob functions, and the ignition lockout module controls the ignition lockout security features.  For optimum power delivery and routing, separate distribution blocks are used for ACC, Ignition and Continuous Power to allow devices to be routed cleanly throughout the car.  These are described in more detail in the next sections.

4.1       Power Organization

For optimal battery life and minimal power consumit was necessary to create 3 separate states for enabling devices in the car: Always On, ACC Power On, and IGN/Run Power On. 


“Always On” refers to devices that are connected directly to the battery.  ACC power requires that a remote three position dash switch be set to the ACC postition for these devices to receive power.  IGN power is applied when the same dash switch is set to the opposite position.  In this position, an LED will illuminate letting you know the car has both ACC and IGN power and can now be started.  Table 1 below shows the devices that become active in each of these states.



Always On








RearView Mirror


Interior Lights

Instrument Lighting

A/C & Heat

Brake Lights

Power Windows

Fuel Pump

Radiator Fans

Power Mirrors

Turn Signals

Radio Memory


Cruise Control

ISQE Controllers

Steering Lock


Table 1. Power Distribution States

4.2       Master Controller

The Master Controller is the switching controller in the system, handling enabling or disabling the appropriate power delivery to the devices that are connected to the respective outputs of the power controller.  A switch must be connected to ground to enable the appropriate output on the Power Controller.  The Master Controller communicates and gets its power from the DB15 cable connected between itself and the Power Controller.


Figure 1 below shows the block diagram of the Master Controller and how the controls in the car are connected to it.


Figure 1. Master Controller Block Diagram


These represent the basic interfaces in the car.  The colors in this diagram represent the actual colors of the wiring used in the car for the respective circuit.  The inputs to the Master Controller require a ground to activate and since the system is FET based, the current draw is in the 100’s of µA for each input.  This equates to much smaller gauge wires to connect the inputs to their appropriate switch controls.  There are several special inputs to the Master Controller that are used for specific control functions of the car.  These and the user defined controls are described in the table below.







MC Special Input

Left and Right Turn Signal LED Outputs

4 Way

MC Special Input

Flashes Hazard Lights


MC Special Input

Used to Turn on IGN Circuits


MC Special Input

Turns on Headlight and Fog Light Outputs


MC Special Input

Turns on Brake Light Output


MC Special Input

Turns on Left Turn Signal Light Output


MC Special Input

Turns on Right Turn Signal Light Output


MC Special Input

Turn on the Starter Output to Start the Car.  Works with IGN input and is locked out 60s after IGN input is turned off.


Steering Wheel

Pushing Horn causes horn to blow.

Hazard Switch

Dash Button

Pushing Hazard button on dash drives signal to RF Controller to flash hazard lights. 

Brake Switch

Brake Pedal

Pushing Brake Pedal closes switch (pops switch out) and activates brake lights

Start Switch

Dash Button

Pushing Start button on dash drives ground to Timed input of Master Controller.  See Start Button section for more detail.

Ignition/ACC Switch

Remote Dash Button

Three Position Switch.  In one position, only ACC power is on.  In the other position, both ACC and IGN power are active.  In the middle position both outputs are off.

Interior Lights

Dash Button / Key Fob

Pushing Light button on dash turns interior lights on (Dome and Footboxes).  Also, unlocking doors turns on interior lighting for short period.

Turn Signals

Steering Column

Left & Right Turn signals are activated by pushing lever down or up respectively.

Parking Lights

Steering Column / Key Fob

Turning knob on lever turns on parking lights.  Unlocking door with key fob will also turn on parking lights for short time.

Hi/Low Beams

Steering Column

Turning knob on lever sets low beams.  Turning it one notch further turns on Hi beams.

Flash 2 Pass

Steering Column

Pulling Headlight lever towards driver causes Hi Beams to come on for duration of time lever is held.

Cruise Control

Steering Column

Setting Lever to ON position enables Cruise Control.  Set/Coast and Resume/Accel will do their respective functions.

Power Window Control

Center Console

Pushing button down opens window while pushing it up closes it.  There are separate drivers side and passenger side switches.

Trunk Release

Key Fob/ Release Latch

Pulling mechanical lever in cockpit “pops” trunk open.  Pushing button on Key Fob drives solenoid to release trunk.

Disarm Alarm

Key Fob Unlock

Pushing Unlock button on key fob disarms alarm.

Unlock Door

Key Fob AUX Buttons

Pulling interior door handle or pushing Aux button 1 (For drivers side door) or Aux button 2 (Passenger side door) on page 1 of the key fob unlocks and opens door.


Key Fob Lock

Pushing Lock button on key fob arms the alarm.  No need to actually lock the doors as they are locked with no power to solenoid.

Table 2. Switches and Controls

Notes: Shaded Region Represents special inputs to the Master Controller

For more details on Key Fob Functions see4.4 RF Controller Section 4.4.

4.3       Power Controller

Power is delivered to the appropriate device when its control input is asserted to the Master Controller, which signals the Power Controller to enable the output driver.  The Power Controller is capable of sourcing up to approximately 20 Amps of current per output.  Each output has a fuse that can be placed, in series, directly on the Power Controller up to a maximum of 20Amps.  Figure 2 below shows how the devices are connected to the Power Controller. 



Figure 2. Power Controller Block Diagram


These represent the basic devices in the car.  The colors in this diagram represent the actual colors of the wiring used in the car.  The Master Controller handles the switching of all these outputs, so when they are not “on” they are sourcing 0 Amps and absolutely no draw on the battery.  This is on of the benefits of using a FET based system.  There are several special outputs of the Power Controller that are used for specific control functions of the car.  These and others are described in the table below.  The total current consumption for each output is also specified which is used for determining the proper fuse to use in the power controller.




Total Fused


Device Current





Used to Power the IGN Circuits in the car and Fuel Pump.  (Does Not Start Car)




Powers Headlights and Fog Lights




Powers Brake Lights (L/R)




Powers Left Turn Signal




Powers Right Turn Signal




Powers Starter Output to Start the Car. 




Powers Horn




Powers Dome And Footbox Lighting




Powers Drivers Side Door Solenoid




Powers Passenger Side Door Solenoid




Powers Gauges (Not LEDs)




Powers Trunk Release Solenoid




Power Window Motors




Gauge Lighting


Rear View Mirror


Power Mirrors




Powers AC & Heater Unit




Powers Radio




Powers High Beams and High Beam LED on Dash




Powers Parking Lights and License Plate Lighting

Table 3. Power Controller Output Requirements

Note: Shaded Region Represents special outputs of the Power Controller

4.4       RF Controller

The ISQE 1000 RF Controller is the heart of the car security and remote control system.  It is completely configurable via a windows interface to behave in the desired manor given the desired set of circumstances.  There are also preset functions that are accomplished by simply connecting the appropriate signals to their respective pins.  The decision was made to keep the functionality simple and not over complicate things.  Figure 3 below shows the basic architecture for the RF Controller.


Figure 3. RF Controller Block Diagram


The colors used in the diagram represent the actual colors used in the wiring of the car.  The table below helps describe the associated functions the inputs and outputs serve.




Max Current




Connects to Master Controller Input, shared with steering column switch.  Used to have parking lights flash when arming/disarming alarm.



Door Triggers.  Shows GND when door either Drivers or Passenger doors are open.  Sets alarm off if armed.



Siren Output.  Chirps Siren when arming or disarming alarm.  Siren will sound when alarm is triggered.



Trunk Trigger.  Shows GND when trunk is open.  Sets alarm off if armed.



Connects to Master Controller Input, shared with interior lighting switch.  Used to have interior lighting come on when disarming the system.



Aux 1 Output is used to control the trunk release solenoid from the key fob.  Aux button on page 2 of the key fob functions.  Configured as a Timed Output with a 1s duration.



Aux 2 Output is used to control the Drivers Side solenoid from the key fob.  Left Aux button on page 1 of the key fob functions.  Configured as a Timed Output with a 1s duration.



Aux 3 Output is used to control the Passenger Side solenoid from the key fob.  Right Aux button on page 1 of the key fob functions.  Configured as a Timed Output with a 1s duration.



IGN Lock.  This is output is connected to the DLRM module and will lockout the Ignition circuits and arm the alarm when pressed.



IGN Unlock.  This is output is connected to the DLRM module and will unlock the Ignition circuits and disarm the alarm when pressed.



Active LED.  LED flashes when system is armed.



Override Button.  Used to disable alarm system and lockout features in case of failure.  Programmed to require being pushed 4 times and held on the 5th button press.

Table 4. RF Controller Functions

4.5       Radiator Fan Control

Since the engine being run is a higher horsepower engine than the standard C5 radiator, it was important to get some extra cooling for it.  A Direct Fit Dewitts All Aluminum Radiator was used which provides a two rows of 1” tubing instead of one, equating to a significant gain in cooling and heat dissipation capacity.  The following figure shows the C5 corvette fan control circuitry as it was implemented in the GTM allowing the PCM to control it and giving both a low and high fan speed. 


Figure 4. Radiator Fan Control Circuitry


The relays allow the fans to both be turned on in low speed mode, but actually spin faster in high speed mode.  Low Speed mode runs the fans in series, hence higher resistance, while High Speed mode run the fans in parallel, higher speed and current.  The diodes are used to protect the fans from large inductive surge currents when the relays switch off.  The current will be sent through the diodes rather than the fans.

4.6       Power Distribution

To help organize routing of power and ground signals through the car, a power distribution plan was used.  The following diagram shows how powers and grounds were grouped and run.


Figure 5. Power Distribution Diagram


As it is seen in the diagram above, the battery uses a large 150A fuse as part of the positive battery terminal.  This gives both protection of the battery and also good contacts for power distribution through the car.  The terminal has a connection for a 4 and 8 Gauge wire.  The 8 Gauge wire is run to the front of the car to power the PCM while the 4 Gauge wire is routed to the starter solenoid, since this is the highest current draw in the car at any one time.  Since the starter is only used to source power during the car starting period, it allows a high current distribution path to the rest of the car the rest of the time, so another 4 Gauge wire is connected to the starter and brought in to a high current power distribution block. 


From there power is distributed through several 8 Gauge outputs of the power distribution block that power the Power Controller, Alternator (via a fuselink cable) and two additional power distribution blocks.  One is used to power the radiator fans, via 3 fused 12 Gauge wire outputs, while the other is used to power the RF Controller and the radio memory functions.  These allow for simpler routing of power.


From a Hidden Dash Switch that controls turning the car power on, one side drives a low current power distribution block for accessory power while the other side of the switch drives both the low current accessory power block and a separate low current ignition power distribution block.  This prevents the car from being started in the case of the alarm being off, and someone being in the car.  The start button will not work, because you won’t have ignition power to the appropriate circuits.  Also, if you wanted to turn on just accessory power, the radio for example, while working on the car, the other position on the switch gives you that opportunity.


There is a medium current distribution block that is used for controlling certain accessories in the car that are run off the power controller PC-8 output.  The Gauge LEDs, Rear View Mirror, and power mirrors are powered off this output.

4.7       Dash Wiring



Figure 6. Gauge Cluster Wiring

4.8       Power Doors and Mirrors


Figure 7. Power Mirror and Window Wiring

4.9       Wiper Control


Figure 8. Wiper Motor Control