Troubleshooting P.L. Error with Tekonsha Primus IQ Brake Controller on Toyota Tacoma

Updated 12/09/2019 | Published 12/08/2019

Question:

Installed wiring harness on my Toyota Tacoma and like I was careful and very sure of the work well done. When I attached the system to battery and I looked at the controller it was blinking P.L. your troubleshooting chart reads Power interruption while brake pedal is depressed. I do not have a trailer to attach to the truck until Dec. 27th. Im buying a camper trailer from a guy that lives in a different state. So I need the system working and all the bugs worked out be fore I leave. What can I be doing now to be sure it working with out a trailer. I purchased all of the harness from you guys and watched your veto that was great. Also I can roll thru the Typical boost and set on 6.2 let off and it starts blinking P.L. I dont know what to do next .Please help

asked by: Robert D

Expert Reply:

As you mentioned in your question the P.L. error code on the Tekonsha Primus IQ Trailer Brake Controller # TK90160 indicates some sort of power interruption. In our experience this seems to be typically caused by a poor ground connection.

You will want to make sure that the white wire from the Primus IQ is securely attached to the negative terminal on the battery for your Tacoma and that it hasn't come loose at all. If this connection is sound and the error code persists, it could also be a bad connection with the power wire.

On the power (black) wire from the Primus IQ make sure it's properly run and connected to the positive terminal of the battery via a 20 or 30 amp breaker.

This should hopefully clear that code so the controller's back in working order, but if not please just let me know and we can continue to troubleshoot.

expert reply by: Chris R