Posts Tagged ‘cars’

Car Hacking: Permanent fix for Civic cruise control switch

October 7, 2012

A few months ago, the cruise switch on my 2007 Honda Civic changed from a toggle to a momentary; the mechanical latch in the switch failed. This switch acts as a master enable for cruise control functionality, so the latch failure meant that I had to hold the switch down to use cruise control. The options to fix it were to pay someone two to three hundred or more to do it for me, pay over $80 to get a new switch assembly and install it myself, or attempt to solder a resistor that cost me a penny years ago into the right spot. Only that last option can ensure the problem will never happen again. I figured that if I was going to take apart enough of the steering wheel to replace the switch assembly, I may as well do a little more disassembly to put in the resistor. As far as I’m concerned, all that disassembly is the hard part; figuring out where to put the resistor and soldering it there should be relatively simple. So I did, and it works; it is just like the switch is always down. Since I pressed down the cruise switch for the last time before it broke maybe a week after I got the car and then left it there for years, the fix works just fine for me.

What follows is how I did it. The specifics are for the car I have, but the general concept will likely work for many other cars, too. The first part is disassembling the steering wheel; skip to part 2 below if you don’t have something similar to an 8th generation Honda Civic (2006-2011 models). If you so have something similar (an Accord may prove similar enough) and already know how to take apart the steering wheel, skip to part 1.

I took a few pictures of this process that do not appear here. You can find them on Flickr.

Warning: I will not take responsibility for anything that goes wrong should you attempt to make the changes I document below. Good luck!

Part 0: Disassembly of the steering wheel

Caution: This assembly contains an explosive initiator.

The first step is to disconnect the car’s battery by taking off the negative terminal connection only. After that, remove the air bag. Without power, the air bag cannot deploy. The air bag is in an assembly with the horn switch in the center of the wheel. It is secured by two bolts with Torx-style (ISO 10664)  heads, both of which will need a good deal of torque to remove. You may want to see if you can loosen one before disconnecting the battery. I had to use my drill, which doubles as a very bulky and torque-y electric screw driver. The bolts are on the right and left sides, and are placed parallel to the ground and perpendicular to the car’s direction of travel. There are no covers and they are the largest bolts on the steering wheel, so they are easy to spot.

After the bolts are removed, the air-bag-horn assembly will rest in place. It is still connected by two wire connectors. The first is accessible from the underside of the wheel. There is a panel easily removed with a flat head screwdriver; remove it. Inside is a yellow wire connector for the air bag that is made to ensure a proper connection and ensure that it won’t come loose. At one end is a black slider; slide it closer to the end and then pull the ends apart. It should disconnect easily, but will resist until the slider is moved. The connector is keyed so that it only goes together one way.

From the top side, regular driver’s perspective, pull out the air-bag-horn assembly. Next, move its end of the yellow connector around some plastic stuff to avoid pulling on the wires. After that, disconnect the other wire. It is green with an odd connector that has a strip of exposed metal. On the black plastic of the connector is a little button and the text “push” next to it. It might be hard to see if you aren’t looking closely or have poor lighting. When pushed, the metal strip is easily removed from the plastic end. After this, the air-bag-horn assembly is completely disconnected.

The wheel is sandwiched by two plastic covers. The cruise switch assembly is attached to the front plastic cover, so that is the next item to remove. It is held in place by six screws from the back side of the wheel, and two more made accessible by the removal of the air bag. These are also two sets of screws; the two from under the air bag are different from the six on the back of the wheel. Start with the easiest two. These are on the bottom middle of the wheel when the wheel is positioned level, like for moving straight ahead.

Hard to find screw

Hard to find screw

The remaining four are difficult to get at. There are two on each side of the wheel that are found easily by looking for a cylindrical well; a screw is at the bottom. I found I needed to turn the wheel so that I had room to use a screw driver (the drill is far too large). I had to use the space in front of the lower instrumentation panel, the one with the tachometer, to fit the screw driver. If you need to do this, I suggest placing a soft towel in front of the instrumentation panel to avoid scratching it. I found that the other two screws are hard to find when looking at the back of the wheel. It was easier to find them by looking from the front of the wheel through the opening made earlier in this disassembly. Looking from the front also made it easier to guide the screw drive to the screw head.

The final two screws are a little more obvious; you may already have found them by this point. One is up and to the left of the trademarked word “Honda” in the appropriate font. To the right is a white label stuck on, and further right and up is the other screw. After removing these, disconnect the wiring harness in the center of the wheel. There a tab to secure it on the center bottom of the connector. Now the front plastic piece can be removed.

Part 1: Getting to the cruise switch

Cruise control switch assembly

Cruise control switch assembly

The cruise and audio controls are in separate assemblies attached to the front plastic piece and held by two screws each. Disconnect both sets of controls. The plastic cases of each are held shut by four clasps, two each on the top and bottom. I had to use a couple of small flat head screw drivers to release the clasps. Once you’ve done this on the cruise control set, you’ll see two circuit boards connected by a ribbon cable.

The board on the right is the one connected to the wires that leave the control’s case. Remove its two screws. After this, the board isn’t really secured to the case, but it still won’t move far because the incoming wires are held in place by a zip tie. Destroy that tie so the wires are no longer secure. So far as I can tell, there is no need to replace it.

At this point, you should be able to pull up on the incoming wires and move the board away from its case. This will reveal the cruise switch; it is soldered directly to this board.

Part 2: Grok what the switch does

Cruise control switch assembly

Cruise control switch assembly

If you just want the solution I found for an 8th generation Honda Civic, skip to part 3. Be warned, however, that the cruise control switch assembly could change, even for the same car. For instance, if the switch that Honda was using when my car was built is no longer available, a new assembly could be made with a different switch part. Such a change may give you different results even if the different control assembly you have can work without modification in my car.

When the switch is depressed, it will either create continuity between two or more of the switch’s connection, or break continuity. This fix only works when continuity is made by the button press; this is likely the more common than breaking continuity.  The continuity signals to the car’s computer that the button is depressed, and then the computer will respond to input from the other cruise control switches. This fix places a resistor across the switch’s connections that have continuity only when depressed thereby causing the computer to see the switch as always depressed.

The next step is to figure out which of the switches output have continuity only when the switch is depressed. The best way to do this is to poke around the circuit with a multimeter set to signal continuity while changing the state of the switch. In the case of what I was working with, the switch has six through-hole connections on the board. The two in the middle always have continuity with each other because the circuit on the board connects them. These have continuity with the pin in the upper left only when the button is depressed.

Part 3: Modify the circuit

Cruise control switch fix ready for solder

Cruise control switch fix ready for solder

A resistor that makes the same electrical connection as is made with pressing the switch must now be put in place. I chose a resistor over a wire because a resistor will limit the current; if anything goes wrong, there won’t be much power to make matters worse. I think anything between 100 and 1000Ω will likely work. I used a 470Ω resistor because I have a bunch of 1/8 watt 470Ω resistors. The 1/4 watt variety often found at any store selling components will work, too, but I figured a smaller 1/8 watt one would be easier to work with.

Cruise control assembly with switch fix applied

Cruise control assembly with switch fix applied

I followed the traces on the board to see where I could put the resistor; it doesn’t have to be right next to the switch. I chose to place the resistor close to a wire connector on the board because it looked like it would be easier to solder the resistor there. I used the leads on the resistor to hold it in place while I soldered. After soldering, I removed the extra length on the leads to avoid shorting the circuit. I also retested continuity on the switch to be certain that the resistor was now part of the circuit and that its addition was the only change.

Part 4: Reassemble & final test

Put everything back together. Reconnect the car’s battery as the last reassembly step. Turn the key in the ignition and stop just short of starting the car. At this point, at least with a Civic, the dash light indicating that cruise control is enabled should be lit, and pressing the cruise switch should have no effect.
All done, or just starting


The Barret-Jackson auction when seen as a car show

April 12, 2009

I went to the auction this weekend to look at the interesting cars rather than to buy something other than Mountain Dew. There were lots of great looking cars. Old ones, new ones, exotic ones, and odd ones. I took over 600 pictures in two days. I would have liked to have gotten a history lesson in the development of the combustion engine or suspensions using some of the examples there, but that wasn’t what the event was about. I’m sure there were people on hand with all the knowledge, though.

Sold in the auction on Saturday was the Batmobile, as seen in one of the earlier movies without Adam West. It turns out that the Batmobile is a 1973 Buick Gotham Cruiser. I like how next to where the gas goes is a label that reads, in quotes, “JET FUEL”. The quotes are very important since you’re supposed to use your imagination rather than real jet fuel. The car went for $110,000.

In the odd category was a 1959 BMW 600 Limousine. It is a small car shaped like a short loaf of bread. Its most distinctive feature is its front door; no hood or engine in front of the driver, just a door.

In the building where they collected tickets, Ford and GM were attempting to sell their new stuff. GM just had several cars around and a couple people to sell t-shirts. Ford had lots of cars, mostly Mustangs, a number of people to answer questions, and a stage setup with two Mustangs for a simulated drag race. GM’s display felt dead by comparison, especially when the sound of those Mustangs spinning their wheels on stage reverberated through the building.

At the other end of the fair grounds, the Ford/GM competition continued, this time with cars going around a short track. I drive Ford’s V6 Mustang around the track, and wasn’t much impressed. The suspension seemed to work well enough, but I didn’t get the acceleration I expected from a muscle car. The Ford representative who was in the car with me touted the engine as a powerful one, delivering 210HP, and seemed to think I might need to be extra careful because of that. I decided not to mention that the car I own delivers just 13HP less, and didn’t heed his warning. At the start of my run through the track, I floored the accelerator pedal, and . . . wait for it . . . wait . . . got some power. There was a noticeable delay, no more than a quarter of a second, before the throttle responded. It was like the car was asking me if I was sure I wanted to accelerate. My brother, a former Mustang owner, tells me that is normal. When Honda gave their 2006 Civic Si the same kind of throttle lag, there were lots of complaints. Honda almost eliminated the lag with a firmware update that was included on the 2007 models and made available to the 2006 owners. Ford evidently thinks the lag is perfectly fine since they have left it in the Mustang for a few years now. Anyway, I’ll keep my Civic. The driving experience on my way home was better. I probably shouldn’t disclose the details.

Ford did do better with their F-150 Raptor ride. A professional driver took me for a trip on an off-road course that included some fast turns and ramps. The truck would get airborne after flying over the last dirt ramp. While on the ride, I kept wondering how the truck didn’t fly off the track, and how it survived all those jumps. It was like a roller coaster ride. Overall, the truck and the driver were quite impressive. I stick to the roads, though, so no sale. If that should change, I’ll need to look at something like that Raptor. I fear I might roll an average truck; turns are just too much fun.

After that, I went to the GM side. I was the second to last person allowed in for the day, which was a good thing. GM was a bit more careful who they allowed to drive; everyone had to take a breath test for alcohol. Such drinks were served at the event, and both Ford and GM used the same track, so I’m puzzled as to why Ford didn’t also do such a test if GM is doing it for liability reasons.

First, I drove the Solstice. It had a four cylinder turbo-charged engine with 240HP and handled well on the track. Some people at the event seem to discount the car because it doesn’t have at least six cylinders, but power is what accelerates. It also did not have throttle lag, although, like all the cars I got to drive at the event, it had an automatic transmission. I’m not a big fan of them, but it makes sense for such an event.

Next, I drove the Camaro. I think it was the 2010 model. It had a good bit more power than the Mustang I tried, although Ford does make more powerful models. The Camaro handled well, accelerated well, and didn’t have throttle lag. I’m not used to its long fairly level hood, but I’d only have trouble with the limited visibility in traffic, and I’m sure I’d cope. I can’t say I’m a fan of its looks; it’s like an evil car for a villain. A villain who needs speed will not be disappointed.

Finally, I was treated to one of the last rides on the Corvettes for the day. Three were on the track and ran it together, like a race. Naturally, this was done by professional drivers. I don’t know if they were using a special model of the Corvette that GM doesn’t sell for use on public roads. Whatever model it was, it gave an incredible ride with the help of a driver who knew how to use it. The drivers were having a little extra fun at the end of the track because by this time they were the only ones on it. Lots of power and plenty of traction. I could see myself enjoying one of these if I ever have money to burn.

It seems Ford had the better marketing, but GM brought the better cars. Unfortunately, a better product isn’t enough. GM may pass away, but I still won’t get a Mustang.

I am Ling, Chinese Human Female UK Car Expert

November 23, 2008

I accidentally resorted my email and found this gem from May 2006. It starts:

Hello, I am Chinese Contract Hire female human expert, Ling Valentine.

Oh, a female human expert. I could use some help from one of those!

I am unique in the UK!

There must be copies in several other countries.

I bring you best UK car takeaway service menu!

It is the Chinese car takeout service. The first car leaves you wanting a second.

I have 290 customer letters on website to prove I am not flying-by-night company. I sell 1.25m cars/month.

Testimonials on a web site are proof she can sell everyone in the UK a car within two years. Does your toddler have a car yet?

NEW FEATURE “There is no free lunch” – YES THERE IS! I bring you free lunch. Nowhere else give you this offer! – Ling

Did you forget that Ling wrote this?

Who is Jeremy Clarkson? I exterminate!

Someone better tell Jeremy Clarkson that a Chinese Dalek is coming to get him. Looks like his opinions have earned him international and interstellar ire.

I test drive cars myself to give you idea of quality and speed.

You no test drive!

This is my Chinese Nuclear Rocket Truck 6×6 7.0 V8, I park it next to A1(M) at Darlington

I think we found Bond’s next mission objective.

False Steps

The Space Race as it might have been

You Control The Action!

High Frontier

the space colony simulation game

Simple Climate

Straightforwardly explaining climate change, so you can read, react and then get on with your life.