Way of the FiST: AEM’s CD-5 Digital Dash Display Put to the Test

A digital dashboard can offer a lot of versatility when it comes to gauges and data. Programmable shift lights, lap timing, logging, and GPS track mapping are just a few things digital logging dashes can accomplish. With the advent of the OBD-II port, now standard on every new vehicle, cars have tons of data that can easily be tapped into to access information to make a digital dashboard work. Plugging a wire into an OBD-II port under the dash is easy. However, the programming to make the information you want to see show up often requires skills most of us who didn’t attend Cal-Tech honestly don’t possess. Good news, other nerds have already done this work for us. The folks at AEM Performance Electronics constructed a digital dash that they claim, “Is the last dash you will ever need.” To find out if this claim was true, we decided to drop one of their digital dashes in our FordMuscle.com project Fiesta ST and see what it could do.

We ordered the CD-5 mounting bracket and RAM ball (AEM part # 30-5545) and used a RAM Mount suction cup kit for sticking the AEM dash to the windshield. The large RAM ball that came with the AEM kit wasn’t used (too big), but the RAM suction cup kit came with a replacement so we had what we needed to make it work.

AEM Performance Electronics makes two different size digital dashes, the 5- and 7-inch. Some dashes have logging capability and GPS mapping capability. Since we’re using ours for racing we decided to order the “Cadillac ATS-V” version of AEM’s digital dashes (small, but with all of the bells and whistles) and chose the five inch model with GPS titled: the CD-5LG Carbon Logging Display with Internal GPS (AEM part # 30-5603).

One reason we chose this particular model, the CD-5LG, was because we didn’t want to permanently install it in our car. Because this thing has such huge capabilities for lap timing and predictive timing we wanted to easily move it from one track day car to another. With that in mind we chose the smaller 5-inch dash, so it could fit in numerous cars. We ordered some specific bits from AEM to make this dash extremely portable. First, we added the plug-in 12-volt power source (AEM part # 30-2227) for juice and the OBD-II cord (AEM part # 30-2217) for data. Then we picked up the CD-5 mounting bracket and RAM ball (AEM part # 30-5545) so we could quickly mount this setup into any car with a suction cup. We also purchased two other components outside of AEM to help with the portability of the setup: a RAM Mount suction cup and arm for the windshield ($70) and a momentary switch ($12) for telling the AEM CD-5 where the start/finish line was on a race track.

You will need to add a momentary switch and wire it into the AEM CD-5 digital dash in order to set a start/finish line of a race track. One wire splices to ground (black wire) and one wire connects to the purple beacon wire from the AEM CD-5.

Plugging In

The concept is simple enough, connect the AEM CD-5 to the suction cup on the windshield, plug in the 12-volt power, connect the OBD-II wire to the OBD-II port under the dash so the AEM reads data from the vehicle, throw the magnetic GPS antenna on the roof and you are off to the races. That all sounds good until you open the box from AEM and start sifting through a lot of wires which can be a little intimidating. Luckily, I had access to technical guru, Hunter Brabham from the AEM Sales Development team, to calm me down. Hunter chuckled when I called him in a panic, “What connects to the purple wire?” With a few details, he helped me understand the system is almost fail-proof.

The main wire harness plugs into the back of the CD-5. The 12-volt power source and OBD-II wires plug into the main wire harness (the plugs are different so you can’t mistakenly plug the wrong one in). The GPS wire (antenna) and USB wire (for programming with a laptop) plug directly into the AEM CD-5. The momentary switch has two wires and connects to the purple wire (the GPS beacon wire) and splices into the ground wire (black wire). That is it. This thing is ready to slap into any car that has an OBD-II port.

With the OBD-II port connection, the GPS antenna, the 12-volt power source, the USB wire (for programming), the momentary switch and a bunch of zip ties we laid out the wiring for a quick and easy install. This is our setup for the Ford Fiesta ST but can be put into most cars with these wire lengths.

We used our RAM Mount windshield suction cup mount to place the AEM CD-5 into our Ford Fiesta ST project car. We have been building this car for SCCA autocross competition as a part of the “Way of the FiST” series. We found a sweet spot just right of the OEM gauge cluster where the AEM CD-5 fit nicely. The 7 inch version (the CD-7) would have been a tighter fit in the little Fiesta.

Using a simple RAM Mount with a suction cup we were able to safely and securely attach our AEM CD-5 digital dash to the windshield of the Fiesta ST. There is no data on the screen yet, as we hadn’t connected the Ford data to the AEM to read channels.

The OBD-II port on a Ford Fiesta ST is easily accessible. It is located under the dash on the driver’s side, just left of the steering wheel. We plugged in the OBD-II cable to provide CAN-Bus information from the Ford ECU to the AEM CD-5. To power our AEM CD-5 we plugged in the 12-volt power supply which came with a nifty on-off switch. This is a nice feature, as many vehicles have constant power to their cigarette lighter ports. This way we could power off the unit when the car wasn’t being used without unplugging anything.

Because we wanted to be able to use this setup in multiple cars, we chose to add the 12-volt power supply option (AEM part # 30-2227) to our AEM CD-5 digital dash. It simply plugs into the center console 12-volt power supply of the Fiesta ST.

The Setup

To collect track map data, lap times, G-forces, and GPS speed, we slapped the magnetic GPS antenna to the roof. We just left the passenger side window down to route the wiring out of the open window. The only drawback to this setup is if someone (me) forgets about the cable routing and opens the passenger door. We dragged the GPS antenna across the roof a bit (whoops!). The GPS antenna placement depends on how nerdy you want to get about GPS data, I like to have it exactly over the center mass of the car. The reality is, anywhere on the car will work for most applications as it is just measuring movement.

The GPS antenna is the easiest part of the installation. Simply drop the magnetic antenna on the center of the roof and you are good. I prefer the placement of the GPS antenna at the center mass of the vehicle, which is normally center of the roof, just behind the trailing edge of the windshield.

Once the AEM CD-5 was installed in our Ford Fiesta ST, it was time to connect the dots between the Ford ECU and the AEM dash. For this, we used the free-to-download AEM Dash Design software and a laptop. This step was very simple to do, even for those who didn’t get accepted into Cal-Tech. Once the AEM is powered on, the vehicle is running, and the USB cable is connected to a laptop with the AEM Dash Design software running, go to the top menu bar and search for “Tools.” Drop down to the third choice at the bottom, titled “Scan Vehicle OBD-II.” Click that and the software will search for the data coming through the OBD-II port and connect it with the gauges on the AEM CD-5. When I did it, it worked on the first shot, and immediately my engine’s RPM were showing up on the digital dashboard. Awesome!

Instead of cruising around the paddock with my laptop on the front seat, I set up this programming table to comfortably program my AEM CD-5 for the options I wanted. I used a portable 12-volt power source to power up the dash and then used the USB cable connected to my laptop to program the dashboard.

Once I had data flowing through the AEM CD-5 and information I could use, I wanted to play around with the custom settings in the AEM Dash Design software. The adjustability is massive in this software. You can use template dash designs already available in the program or adjust and design your own. Lawson Mollica, Director of Marketing and Public Relations for AEM, talked about the endless designs available in the AEM Carbon Display digital dash packages, “we said this is the last dash you will ever need, and we mean it.”

According to Lawson, the information coming out of modern cars combined with the programmability of the AEM dash is the perfect combination to provide any custom dash an enthusiast wants. Essentially, the dash will take you as far as your imagination will let you. With this much adjustability, the first thing I did was use the AEM Dash Design software to create a custom splash screen (the first image that shows up on the screen when the unit is powered on) with the logo from my race team Double Nickel Nine Motorsports. How about that for custom when you fire up your race car dashboard?

When the AEM CD-5 powers up, this is the first thing that pops up – the team logo for DNN Motorsports. I included a little mantra from our team, “Refuse to lose.”

The next thing I wanted to program, and I was super excited about this component of the AEM CD-5 dash, is the progressive shift light. First thing to know about the AEM CD-5 as it comes out of the box: the shift lights are set to the default setting of staring directly into the sun. If you are driving your car at night and the shift lights come on, you will essentially be blinded for a moment. This is not good. No problem though, while in the AEM Dash Design software click on “Setup,” then “Brightness,” and move the settings down from 100-percent to something more reasonable. I have found that 65-percent for normal mode, and 40-percent for night mode works great. To set the shift light RPM, go to “Setup,” then to “Shift Lights” and then type in your inputs in the spreadsheet. As you increase RPM, the lights will start to progressively come on and then all of them will flash at whatever RPM you choose.

My favorite part of the AEM CD-5 is the progressive shift light. Programming it is extremely simple. Put in the engine RPM you want for each light to come on. Send that program to the AEM CD-5 dash and rip through the gears.

Once you have setup how you want your AEM CD-5 to display based on the information the vehicle reads from the ECU via the OBD-II cable it is time to send that information from the AEM Dash Design software to the AEM CD-5 unit. This is a very simple step, just go to “File” and then drag down to “Upload To Display.” A new window will open; click “Upload.” That will send the data through the USB cable right to the display. Done!

When your AEM Dash Design software has completed uploading the newest version of your custom dash display to the CD-5 this is the screen you will see indicating the process is complete.

The Fun Part

With my AEM CD-5 programmed and setup in the car, I was ready to go out and have some fun. What I found was most of the stuff worked like it should: RPM, shift lights, and engine temperature. However, some things weren’t showing up like oil pressure and lap times. A quick call to Hunter Brabham helped me fill in the gaps. As far as oil pressure goes that information is not available from Ford on the CAN Bus. Other manufacturers do provide that information. That was unfortunate because I wanted to setup one of the AEM alarms for low oil pressure, however, without data from the oil pressure sensor, I cannot setup an alarm based on a certain pressure setting. Oh well, my stock dash will tell me that anyway. Time to go concentrate on things I can change. My next issue was the start/finish line wasn’t setting. That one was an operator error based on the settings in the AEM Dash Design software. I plugged the USB wire back into my laptop, made the following changes: “Setup,” then “Lap Timing / GPS” and changed the default setting from “Beacon” to “GPS.” Fixed!

One of the things I struggled with initially with the AEM CD-5 was getting the starting line portion of the programming to work. Luckily, Hunter Brabham dialed me in and provided me this screen capture showing what options need to be checked for the starting line to work.

To ensure it isn’t a mystery if you have set your starting line properly or not (or if you wired the momentary switch correctly) AEM includes a light flashing feature. As you drive past the start/finish line and you grab the momentary switch and press down on the button just as you cross the line, hold the button down for a few seconds until you see two lights flash on the AEM CD-5. That is confirmation that your start/finish is set. As you come around the next time you will see your total lap time and “Lap 1” listed on your screen. You are logging laps!

One of the many multitasking tricks when racing (because you are busy behind the wheel) is to grab the momentary switch and hold it down for a few seconds as you cross the start/finish line. For road courses, this isn’t a big deal (start/finish is normally on a long straight). But for tight autocross courses it is a challenge.

Initially, I thought the progressive shift light was the coolest feature on the AEM CD-5. That was, until I played with the predictive timer feature of the digital dash. This feature is epic. After you put one lap in the books, the dash will tell you if your next lap is already faster or slower as you race around the track. This is awesome stuff because it allows you to try different things to attempt to increase speed, and you will find out instantaneously if that change was better or worse. I find myself really concentrating on the predictive timer and pushing harder and harder for a better lap. This feature has certainly made me a faster driver. Thank you AEM.

The predictive timer feature is the single most important thing that will make you a faster driver. As you take lap after lap, the AEM CD-5 will tell you if your current lap is faster or slower than your fastest lap. Think of it like racing against the ghost car in PlayStation’s Gran Turismo. You instantaneously know if something you tried, a new line through a curve or a later braking point, provided you with a faster time.

Once we had the install setup dialed in and a few programming bugs, which were simple to resolve, it was time to hit the track and play with our new digital dash. We chose a local autocross event to drive the car with reckless abandon and see if our AEM CD-5 was worth the effort.

We took our project Ford Fiesta ST and put it through its paces using the AEM CD-5 digital dash. We fine-tuned the shift light and played around with the start/finish line feature.

What we immediately found was that we very much liked our AEM CD-5 digital dash. It was easy to install, provided enormous amounts of important information and it made me drive the car harder around the track. I found myself staying off the rev limiter (which will always hurt a lap time) once I had the shift light perfectly set.

Here you can see all of the shift lights illuminated, telling me to, “Shift now Dummy!!!” as I take a run through an autocross course.

After our autocross weekend was in the books, with a double victory, Saturday and Sunday, in the SCCA H-Street class, we came home and started to look at the logged data saved by the AEM CD-5. We took that data and overlaid it on some GoPro footage to create the video below of one of our runs. You can see speed, a friction circle showing G-force direction, and a track map.

This was the first time I was ever able to plot GPS data on a video, and I think it came out really cool. The GPS data is especially helpful for an autocross course where there is no track map available, as the courses change at each event. With this feature, I will be able to view a map of the course and see where to turn left and where to turn right. I will also be able to see where I can push harder for the next run. This is the sort of information that can make you a faster competitor.

Our conclusion on the AEM CD-5? We like it. It was easy to install, easy to program, and made us faster around the track. That is a win.

Lawson from AEM told me this would be the last dash I would ever need, and with the testing we completed with it, he may be correct. We can plug this into any other vehicle, have the AEM Dash Design program read what is coming out of the OBD-II port, and with about five minutes of adjustments, this thing will be ready for our next car. The question is…what kind of car will that be? Whatever it is, it will certainly be logging data through our AEM CD-5.

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Rob Krider

Rob Krider will race absolutely anything. He is a multi-national champion racing driver and is also the author of the novel, Cadet Blues.
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