MAN# 650264:B
Operation
The electric cooling fan controller provides a way to run up to two electric engine cooling fans or one two speed cooling
fan. (A second relay, sold separately, is required for two speed or dual fan operation). The controller monitors the engine
temperature using a dedicated sender, or a gauge and its sender. When the engine temperature goes above a user
adjustable set point, the fan is turned on with a relay. When the engine has cooled below a user selectable off
temperature, the fan is shut off. Separate on and off temperatures can be set for the high and low fan outputs. The
controller will also run the fan when the air conditioner requires, by detecting when the air conditioning clutch is engaged.
The unit can be set to keep the fan running (if the engine is hot enough) after the key is turned off. Several delay times are
available from no delay to five minutes. The display will countdown the seconds left before the fan is turned off. If the
battery voltage drops too low, the fan will be turned off and a “Lo bAt” message will display for the remainder of the time.
Settings for several gauge systems are included to make installation with a gauge easier. The included gauges are
Stewart Warner, Classic Instruments, VDO, and Autometer. If the gauge being used isn’t included, a custom calibration
option allows the system to be calibrated to any gauge with clear numerical temp markings. This is accomplished by
setting the controller to match the marks on the gauge with a few steps described in detail in the installation instructions.
IMPORTANT NOTE!!!: If using a gauge with this unit, always ensure that your gauge is working properly. If the gauge is not reading
correctly, the fan control unit will not have correct temperature information and cannot be guaranteed to properly control the fan,
possibly leading to overheating and engine damage.
If the gauge uses a two-wire temperature sender (such as Autometer full sweep) use of a dedicated Dakota Digital sender is
required.
If a gauge is not used, ONLY a Dakota Digital 300ºF sender should be used. Other senders may not give a correct reading to
the control unit.
Custom gauge calibration requires numerical marks, stock “C-NORMAL-H” type gauges cannot be accurately calibrated to.
Required components for installation:
The PAC-2700 is shipped with necessary components for use with a single fan on a gauged system. These parts include:
1
PAC-2700 module
1
RLY-3 relay with wiring harness
1
Instruction manual
For some options of the PAC-2700, additional components are required. These are listed below.
- Second RLY-3 assembly (needed for dual fan or two speed fan operation)
- 300ºF sender Dakota Digital temp sender (for operation without a gauge)
Installation
Note: Mount ONLY in vehicle cabin. Controller is not designed for engine compartment mounting.
The terminal strip on this unit has 6 connections:
1. Fan high relay
Connect to the white wire on the high fan relay assembly
(for single fan applications leave unconnected)
2. Fan low relay
Connect to the white wire on the low fan relay assembly
3. Ground
Connect to a good chassis ground
4. Power
Connect to a fused 12V battery
5. Sender
Connect to the engine temperature sender wire.
6. A/C clutch
Connect to the cycle switch on systems with air conditioning
(on systems without air conditioning leave unconnected)
7. Ignition
Connect to a circuit which has +12V only with the ignition key ON. (switched power)
Relay wiring:
White
Connect to control unit
Green
Connect to fused 12V battery circuit that can run cooling fan
Red
Connect to fused 12V battery
Black
Connect to cooling fan
Factory Presets
This controller comes preset to use a dedicated sender as follows:
Dakota Digital Sender only (no gauge, see above for 300ºF sender options)
One single speed fan
205ºF on temperature
200ºF off temperature
30 sec Fan off delay
If the factory settings don’t fit your application, you will need to go through the setup procedure on the following page. At
anytime during the setup procedure, the key may be turned off and the settings up to that point will be saved.
