Expert Answers about Toyota Highlander

• Troubleshooting Pre-Collision System Malfunction with Primus IQ Installed on a 2017 Highlander
• I spoke with my contact at Tekonsha who knew exactly what you were talking about. He said that the best solution for installing a brake controller like the Primus IQ # TK90160 in your 2017 Toyota Highlander is to install a diode on the red wire of the wiring harness for the Primus IQ. This is the wire that connects to the cold side of the stop light switch. To prevent the 12V from backfeeding into your Pre-Collision System he recommended using a diode rated for 1 amp. These are not very...
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• How To Find The Trailer Lighting Fuse In The Fuse Box Of A 2020 Toyota Highlander
• I was unable to find a diagram of the fuse box online for your 2020 Toyota Highlander but if you look at the lid of the fuse box it will have a diagram explaining where each fuse is and its function. You can use this to find the trailer lighting fuse for your vehicle. The picture you referenced, which I've also attached below, is for a 2020 Toyota Highlander.
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• 7-Way Trailer Wiring Connector Recommendation for 2022 Toyota Highlander with 4-Way
• We have a 7-way kit that is custom fit for your 2022 Toyota Highlander with the part # TK57VR or for a different option we have the 7-way adapter part # 37185 which your current 4-way will plug into that you'd need to run the purple wire to the reverse light circuit of the Highlander.
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• Trailer Left Turn Signal Not Working with Curt Wiring Harness Installed on a 2008 Toyota Highlander
• I tried to find an online copy of the owner's manual for the 2008 Toyota Highlander but it was not available. Check your owner's manual to find the fuse locations to determine if there is one for trailer left turn signal/brake lights. If it is not a fuse, then there is a way to test the converter # C56217. Use a circuit tester such as # PTW2993 or your meter to test the yellow input wire (on the side that has more wires going into the box) while the left blinker is activated. If there...
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• Can Curt Trailer Wiring Harness # C55400 be Used with LED Trailer Taillights
• The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C55400 that you referenced works perfectly fine with trailer lights that are LED.
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• How Do I Troubleshoot The Trailer Wiring Of My 2022 Toyota Highlander
• In order to troubleshoot your 2022 Toyota Highlander wiring installation you will need some tools to assist you. You will need a 12V circuit tester. I recommend the Cordless Circuit Tester, part # PTW2979. In addition, you will also need basic wiring tools, electrical tape, a wire stripper, dielectric grease, and wiring fasteners. Troubleshooting your trailer wiring can be very intensive. This can be caused by a number of issues. If you have a plug in harness, it may be for models with...
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• How To Find the Trailer Fuses and Relays On a 2006 Toyota Highlander Hybrid
• If you have a factory plug on your 2006 Toyota Highlander then these circuits will be protected by fuses and relays built into the factory fuse box located under your hood. In order to be sure you are looking in the correct locations you will need to either look in your owner's manual for these locations or there will be a diagram printed on the underside of the fuse box lid with this information for you. If you do not already have the trailer connector portion of the harness then I recommend...
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• Troubleshooting Trailer Lights Staying On All The Time with 2019 Toyota Highlander
• Since you have ruled out the wiring on your trailer as being the issue there has to be some kind of short with the wiring or converter on your Highlander that's causing constant power to be sent back to the trailer running lights circuit. I first recommend just giving the 4-Way itself a visual inspection on the Highlander. Check for any corrosion or debris that needs to be cleaned out even though this is unlikely on a newer vehicle like yours. Then check the brown wire from the back of...
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• Troubleshooting K-Source Universal Towing Mirrors That Folded In When Passing A Semi Truck
• I have not seen any customer feedback stating that the K-Source Universal Towing Mirrors # KS3891-2 have folded in when a semi truck passes by in the opposite direction, although I can see a big rig doing so if the tow mirrors were not completely tightened and secured to your factory mirrors. If the tow mirror itself folded in then I would make sure the screw on the back of the tow mirror is tight to reduce movement - do not overtighten since the housing is plastic. Also make sure that...
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• Troubleshooting Trailer Wiring Running Light Circuit on 2005 Toyota Highlander
• Since you've tested your trailer with a direct 12V power source and confirmed that it is not the problem, I suggest you first focus on the item that is most often the cause for the kind of issue you describe: the trailer wiring harness ground wire. If the ground on the Highlander's wiring harness is not solidly affixed to a clean bare metal surface it may be able to pass enough current for on-and-off signals like brake and turn lights but may not be able to handle the steady current draw...
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• Diagnosing Malfunctioning Lamps on Trailer Towed by 2008 Toyota Highlander
• Since you have tested the trailer with a different vehicle, and everything seemed to work okay, it would seem that you have ruled out the trailer as being the problem. You have tested the trailer connector, and have found that each pin on the connector is showing power when its function is activated, which would usually rule out the vehicle. I would first suspect the ground connection for the trailer connector on the Highlander. Trace the white wire and locate the point where it grounds...
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• After Installing Trailer Wiring Harness on a 2006 Toyota Highlander Sport Trailer Lights Do Not Work
• There are some things you can do to determine if the issue is on the harness, # 118413, or somewhere else. First, make sure that the harness is grounded to a clean metal surface. There cannot be any paint where the harness is grounded. Also, if you are using a factory grounding point that is already occupied by 1 or more items then I recommend moving the harness ground elsewhere. Next you will want to test the wires going into the black converter box and the wires coming out. Use a circuit...
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• What Could Cause Trailer Tires Jumping Off Ground When Empty
• If the tires on your tandem axle trailer are leaving the ground during travel when it's empty there are a couple of things I recommend looking at. The first thing that comes to mind is the trailer's suspension. A stiff suspension can definitely create a rough ride with a lot of bounce especially when the trailer's completely empty. I recommend making sure that the leaf springs are appropriately rated for the trailer and not way over capacity (if you have 3,500 pound axles the springs'...
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• Troubleshooting Rear Sag When Towing with a 2018 Toyota Highlander Using Weight Distribution
• That is a very interesting situation that you're in. I do have some things for you to check to help make sure you are able to safely tow your trailer, but unfortunately there are no aftermarket suspension enhancement options to help level out your 2018 Toyota Highlander. From what you stated it sounds like you are pretty mindful of the tongue weight (TW) of your trailer but it still doesn't hurt to go back and double check what your TW is when the trailer is fully loaded. A portable TW...
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• Vehicle Keeps Blowing Fuses When Headlights Turned on with Trailer Connected
• You're likely on the right track. If your fuses keep blowing out, this is a sign that there is a short somewhere on the system-most likely on the running light circuit. Since you're saying that the trailer has all new wiring-if this was something you installed I would recommend re-checking your wiring to make sure that there isn't an exposed wire (cut, damaged or otherwise) touching the frame of the trailer. The ground wire on the trailer should be checked to make sure it is secured to...
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• 4-Way Trailer Connector on a 2008 Toyota Highlander has Power with Vehicle Off
• The wiring harnesses for the 2008 Toyota Highlander all have power that goes to the converter box so it is possible that the pins could have some power to them all the time. The power may be enough to light the test lamp but is probably not enough to power on the trailer lights. You can confirm this by plugging in a trailer. Curt wiring harnesses have been known to do this but I have not heard of this issue on other brands. You will also need to make sure that if your harness requires...
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• How to Test Powered Module of Curt T-Connector Harness for 2018 Toyota Highlander
• In order to test the powered module of the Curt T-Connector Vehicle Wiring Harness # C56217 you will need to use a circuit tester such as the Cordless Circuit Tester # PTW2979 and test the wires going into the module, and then the wires coming out of the module. If there is power going into the module, but none coming out, that means it could be faulty and needs to be replaced. This harness does have a 1-year warranty. A converter will often go out due to a short in your trailer wiring,...
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• Why Would Trailer Wiring Harness in 2008 Toyota Highlander Stop Working
• If you had the part # 118449 installed in your 2008 Toyota Highlander that would indicate that you do not have the factory tow package. This harness comes with a converter box built into it so I am not sure how you would have actually had this harness installed if you don't have a converter box. If instead what you have looks more like the part # 56042 then you do not have the # 118449 installed. The part # 118449 has an inline fuse on it for the power wire that connects right the port...
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• Troubleshooting 4-Pole Factory Wiring Harness on 2008 Toyota Highlander
• If your trailer lights just recently started malfunctioning, I recommend that you start by checking to make sure that you don't have a blown fuse or a bad relay in your 2008 Toyota Highlander. You will want to check all of the fuses and relays that relate to the tow package. If all fuses and relays check out to be fine, I would then check the grounds on both the Highlander and your trailer. You will want to check to make sure that the ground wire is secured tightly to a clean metal surface...
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• Problems Paring the Prodigy RF Brake Controller with a 2015 Toyota Highlander
• There are a few things you can try to get the unit to pair. First, If you do not see displayed what the instructions say just keep going through the steps. Sometimes, it will not display what it is supposed to but it will still work if you go through the steps to completion. If that does not work then you can try taping off the pin in the 5 oclock position at the back of the RF (where the trailer plugs into) using electrical tape. Then go through the installation process. If that doesn't...
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