Tow-Pro Elite Red Flashing Fault Code

Flashing red Tow-Pro Elite fault code explained

REDARC's Tow-Pro Elite, Australia’s favourite brake controller, has recently had some software updates to ensure it continues to set the benchmark for brake controllers in the industry. These updates are designed to keep you on the road as safe and as informed as possible.

If you are using an Al-Ko iQ7 braking system, a red on/off/on/off flashing sequence has been added to the Tow Pro Elite as a fault code that can indicate a fault of the hydraulic/pneumatic system. Please check for faults in brake lines and electrical supply to the pneumatic pump according to the manual for the iQ7 brake actuator.

If you do not have one of the Al-Ko systems fitted to your trailer, this code can be triggered by a poor earth connection to either your trailer socket or for the control module.

If you have this code flashing, it is recommended to assess the earth wiring on PIN 3 of your trailer socket/plug and controller to make sure the there is a suitable and sound earth connection.

This error code can also be triggered by a poor earth connection on an Anderson plug or PIN 10 on the bottom row a 12PIN trailer plug.


7 pin REDARC 12 pin REDARC


The list of things to inspect is below:

• If you have an Anderson Plug please test the operation of the Tow Pro WITHOUT the Anderson Plug connected (please ensure the Anderson Plug cable is secured before driving). If the problem disappears, the Anderson Plug earth has a poor (high resistance) connection. Please locate where this has been terminated. A good earth is a metal to metal connection, secured with a BOLT. If it is connected to a painted / powder coated surface this will cause the problem. If this does not resolve the issue please see below.

• Make sure the size of the earth cable going to PIN 3 in the trailer socket, and from the plug to the trailer earth in the trailer is of suitable size. Some OEM looms have only 3mm auto cable and with brakes 5mm is a minimum recommendation, go larger if it fits.
• Make sure the trailer socket on the car has an earthing cable location which has a sound link back to the vehicle negative.
For example:
- Don’t use scotch locks to vehicle taillight earth. This may work for a short period but will eventually fail.
- Be careful bolting to the tub of a ute: most modern vehicles have rubber mounts disconnecting the tubs (and in some cases chassis) from ground.

• If using a body earth, make sure there is a bolt to go to and remove any paint on the body that insulate your lug from a good connection. This is the same for both trailer plug and brake controller white wire.

Finally, make sure of all trailer connections.

Check for;
• Dirty or corroded plug/socket. (Usually fixed with a spray of WD40, RP7 Etc.)
• Crushed pins not putting enough spring pressure on the socket (fix using a fine flat blade screwdriver to spread the male pins for better spring pressure on the socket, but be careful with this as some trailer plugs have a hardened or a cast metal and the pins can break off if too much tension is put on them).
• Loose or broken wiring in the back of the trailer socket or plug.


voltage drop tow-pro red flash

For further testing information of the Tow-Pro Elite yellow and purple fault codes are explained here.