Graeme Fletcher / National Post files
Excessive moisture could cause the horn to honk in a 2012 Dodge Caravan.
QUESTION: I own a 2012 Caravan and the horn beeps when it is in my driveway not running or moving. When it happens the door locks go up and down at the same time. I had it into a dealer and had it scanned, but nothing showed up as an error. Have you heard of this before or could you tell me what this could be?
Answer: I would think the horn honking is a secondary symptom rather than the cause of your problem. The factory settings on your Caravan do have the horn honk once when the doors lock, but this can be changed so it doesn’t honk when locking by going into the Settings menu of the Electronic Vehicle Information Center (EVIC), sometimes called the driver information centre. I believe it is the doors unlocking and locking by themselves that are the real symptoms of your problem.
On most vehicles, I would look first at the driver’s door wiring where it passes between the door and the body.
The wiring flexes here every time the door is opened and sometimes the wires break and short together, causing many weird problems. You can sometimes feel a broken wire by squeezing the rubber boot the wires run through.
I say this is where I would look first on most vehicles, but most of the door lock operation is controlled by modules and data communication wires on your vehicle. When you press the driver’s door switch to lock or unlock the doors, it sends a message on a Local Information Network (LIN) data line to the driver’s door module. The door module then sends a message on another two-wire CAN BUS network to the Totally Integrated Power Module (TIPM) — don’t you just love all those acronyms!
The TIPM controls many functions, including horn, door locks, fuel pump, memory seat and any other vehicle features. It is located under the hood on the driver’s side inner fender and has seven large electrical connectors going into it on the bottom side. Connector C5 has the connections to the lock motors and connector C3 has the connections to operate the horn. There are many fuses and relays on the top of the TIPM, but there is also a circuit board inside that has integrated relays that control the door locks and horn.
Past experience has shown that moisture can get into the TIPM and cause corrosion on the circuit board and the electrical connections at the bottom side. This corrosion could be causing the inadvertent locking and unlocking of the doors, especially if the humidity was high. You can remove the TIPM and check for corrosion on the bottom side electrical connections, but if the corrosion is on the internal circuit board, the TIPM needs to be replaced. Just be sure to double check the wiring at the door first to avoid unnecessary expense.
Question: I just bought a newer 2014 Chevrolet Equinox and love the vehicle, but now I am concerned there may be something wrong. It runs fine, but when I have it idling and open the hood, there is a ticking sound that is fairly loud. The ticking sound increases with engine speed. My past vehicles didn’t have this sound and a friend told me it could be the engine lifters, whatever that means? I can only really hear the noise when the hood is open. Inside the vehicle, the nose is almost not heard. What do you think?
Answer: I suspect there is nothing wrong with your Equinox. The engine in your vehicle has direct fuel injection, which sprays the fuel directly into the engine cylinders instead of the intake ports as in earlier Equinox engines. The fuel pressure has to be much higher to spray fuel directly into the cylinders and the operation of the fuel injectors is much louder when controlling this higher pressure. They make a clicking sound that is rapid, constant and increases speed with engine speed, which is what you have described. Drive and enjoy your Equinox.