Electronic Modifications


Not long after the new year 2012 my speedometer cable broke in half inside the jacket. With a dead speedometer the ECM no longer receives a VSS signal and throws on a check engine light after a few kilometres of driving. The engine still runs well but the ECM now senses a problem and holds idle at 1500RPM. I did not want to deal with no speedometer for too long so I began exploring options. Replacing the stock cable would not have been too hard but ever since I put big tires on the truck it has been way off. There was no way to correct this problem even changing speedometer gears would not give me enough correction. So I looked to the aftermarket and when it comes to gauges Auto Meter is the place to go. They have the most options for style and have solved many of the issues with putting non stock gauges in and old car and make many models completely programmable and able to accept many types of input signals. Their programmable speedometer line up can accept square wave, sine wave or pulse signals which covers any type of speed sensor. So I picked up an Auto Meter Sport Comp 3 3/8" electronic programmable speedometer I also picked up the matching tachometer, I was kind of obligated to make it all match! To tackle the VSS issue I simply took one from a 93 Trooper in the junkyard and it screws in right were the stock cable does. It could not be more simple than that!
The stock Trooper gauge cluster actually lends itself very well to an aftermarket gauges since the stock gauges are all housed individually. The Auto Meter line up does not have a style that bolts directly in, but as luck would have it, no drilling, cutting or grinding is necessary to install them. I simply removed the stock instrument panel cover which is held on with 4 screws and then removed the stock gauges. I test fit the new gauges in the instrument panel cover and they sat in the tapered hole quite nicely and the Auto Meter retainers gripped the edges enough to secure them but I added a 10gauge ring that fit tight around the speedometer and tachometer and helped clamp the new gauges in place. So now it was time to dive into the wiring.
The only new wires I had to run were for the new VSS. I followed the wire loom for the stock transmission wiring harness and then passed them through the grommet that was used for the old speedometer cable. The old speedometer was cable driven so it did not have a 12V ignition power source or ground but the tachometer did so I made a harness that spliced into the tachometer wiring and powered up the speedometer and the new VSS. The only wire used from the old speedometer plug was the one for the secondary VSS which sends a speed signal to the ECM. I simply shared the signal from the VSS between the original, secondary VSS and the new speedometer. Then there was just a wire for the light and that's it. Most of the time was spent crimping and soldering all the terminals and making everything neat. The tachometer was as easy as cutting the wires off the old gauge and putting spade terminals on the ends of the wires and plugging them into the back of the tachometer.

Auxiliary Gauges


To match the new gauges in the instrument cluster I decided I would swap all the auxiliary gauges as well. I really like the Auto Meter gauges because they have numbers on the face that actually tell you where you are at, rather than just showing a safe range like the stock ones. The fuel gauge is one of Auto Meter's programmable ones that can be set to work with any sending unit.

CB Radio


When you are on the trail or highway you don't always have cell phone access plus cell batteries don't last more that a couple days without a charge and who wants to make a long distance call to your friend who is 100 feet away just because you are a few hundred kilometres from home? Well the best solution for communication on or off road is a 2 way radio. They are fairly cheap and you don't need a 3 year contract. However some radio frequencies need a licence and that costs money. But not for Citizen Band Radio or General Radio Service in Canada. They are the same thing with different names and run on a 27Mhz frequency with 40 channels. In the early 70's CB use required a licence but by the mid to late 70's the FCC was getting 1 million applications per month and all the rules and regulations were being ignored anyway so the licensing system was dropped and anyone with a radio was free to use the channels. However the popularity of CB lead to its demise. Because so many people were using it and everyone shared the 40 channels they were simply crammed with communication and it was difficult to find a free channel for you and your group to chat on. But today almost no one uses it and every channel is virtually free from chatter and with radios starting at $20 and about the same investment for a basic antenna anyone can chat for $40 in any vehicle.
When I chose my radio I decided to invest a descent amount of money to get something good. Cheap radios work and ALL radios have the same transmitting power as defined by FCC and CRTC rules. So paying more wont mean you can talk over more distance. But better radios allow you to adjust SWR, Channel phase and Mic and Speaker gains. You also have the option of automatic squelch and a feature that will cancel out electrical noise from the vehicles ignition and charging system. Plus the speaker and Mic is better quality and conversation between you and your friends is VERY clear with a quality radio. I have used cheap radios and they just don't sound as good and you find yourself deciphering what your friends are telling you and everybody has to repeat them selves a ton of times.
I picked up a Uniden PC78 Elite which is their top of the line unit. It set me back about $250 but it was well worth it. Friends of mine bought the same one and when we communicate on the trail or highway it is just like they are beside you. Very clear the plenty loud. When you buy a CB radio you need to supply your own antenna and it must be designed for the frequency range you are on. So I picked up a Larson 27Mhz antenna with a coil base and stainless whip. The coil also un screws from its base and can be replace with a dust cap when you don't need the CB radio. Antenna's with the coil at the end of the whip are a bit better but they are much heavier antennas and do not flex as well as the thin stainless whip.
So once I got the radio and antenna home the most difficult decision was where and how to mount it. The Uniden unit is about the size of a DIN1 head unit you would buy for your stereo. So that helped with mounting options. The Trooper mounts its factory DIN1 radio in a metal cage that screws into the bottom of the dash. So I decided that would be a good start for mounting my CB. I picked up a bracket and plastic cover from the junkyard and mounted it beside the factory radio below the glove box. I was sure to mount it at the same height and made sure it was flush with the factory radio. This gave the installation a very factory look and it was very solid. I powered the CB Radio with the same power supply as the factory radio. But I found that when the CB Radio was on the capacitors inside would back feed into the factory radio and keep it running for about 5 seconds after the truck was shut off. The solution was to install a diode in line with the CB Radio so it could not back feed.
Antenna mounting location, cable length and quality of both the antenna and cable all play a huge role in the distance you will be able to communicate. For example I have seen an  antenna mounted on a rear bumper beside the spare tire and the vehicle even had a roof basket. The antenna tip was about 6" below the height of the roof basket. Definitely not ideal. On the roof is a good location but lets face it, your just asking for it to get torn off by low lying branches, covered parking lots or even your own garage. So for most vehicles the front fender mount typically wins out. So that is what I chose for mine. For the antenna I bent up a simple stainless bracket and mounted it with a factory fender bolt and routed the antenna wire along the fire wall and into the cab where it connects to the back of the CB Radio.

1990 Isuzu Trooper - Chilliwack BC