How To Test GEM Module On Ford Trucks

Is your truck’s radio, limp, wiper, and other parts aren’t functioning properly? Or, perhaps the ford GEM module problems are getting out of your hand that needs to be fixed through testing?

The GEM module usually controls most electrical parts of ford’s older models including Ranger, F-series, Mondeo, and others. Most Ford dealers test or program it before treating the fuse issue or replacing the unit.

In this guide, we’ll talk about this topic so that you can easily program it. Let’s see how to test GEM module. Ready!

Table of Contents show

Explaining How To Test GEM Module In The Right Way

In ford trucks, the GEM module can be tested to know whether the signals or data are transferring to the single range attached systems or not. The testing of it is easier if you know the full details of the input, output, and service mode activation process.

While having bad GEM module symptoms signs such as the windshield moving or a light turning on out of nowhere, then it’s the perfect time to test GEM module.

To do the given procedure, be sure to carry a scan tool and digital multimeter as these things help to identify the error so that the problem can be solved sooner. Now, without wasting time, take a look at the ford GEM module testing procedure.

Consider These Before You Start

Turn off the ignition system. And avoid leaving the key on the truck.
Shut down all the electric systems including A/C, limp, radio, and so on.
Use a handbrake to prevent touching the footbrake and acceleration pedal.
Set the gear in N (Neutral) or P (Park) mood.
Close all the doors just as usual.

After doing all of these, you can move forward to the next task.

Warning: Be sure your truck doesn’t make an alarm or noise after completing the procedure as it indicates failure.

Activating Service Mode Procedure

Turn on the switch of the heated window (rear) and press it for a long while.
Start your truck by switching the ignition.
Let go of the heated window (rear) switch
Again, press the switch of the heated rear window 8 times. And, make the duration between 6 seconds.

Now, listen to the sound or look into the signal lamp/light flash that indicates success to activate the service mode.

Testing Input Signal Procedure

You need to make the wiper into the “OFF” setting to continue the given steps. That way it will be able to do the test and give GEM module information properly. After that, you should activate the given controls to do the test. And these are:

Left/Right or turn signals
Warning light aka “Light ON”
Windshield rear and front wiper
Wash system of the windshield (both rear and front)
Open/closed door system
Central Lock (If offered)
Open/closed hood system (for ford trucks that has an anti-theft alarm system)
Heated window (front and rear side)
Front and rear heated windshield

Check if signal lamp flashes and acoustic sound alerts are indicating or not to confirm testing of the input signal by GEM module.

Testing Output Signal Procedure

Change the wiper switch to the “Intermittent” setting before you test the output signal. If you don’t know, then pressing the rear window heater switch helps to turn the given controls on or off.

Front & rear windshield wipers
Rear Heated window
Interior lights (Turn it in “ON” position)
Heated windshield (During the time when the engine is running)

After that, check if it has done testing the above controls. And, if you see the heated window switch is turned on again, then try to restart it with the “A” point to bring back functions in the right order.

Departing From Test Mode

Even though the GEM module usually turns off the service mood in 20 seconds, still it’s better to end the process by yourself. After coming to this far, let’s drive into the method:

Turn on the heated rear window switch and press it for a good while.
Switch off the ignition.
Release the switch that you’ve holden for too long.

You will now see 3 signals including sound alerts and flashes of signal lamps that is confirming the service mode has ended.

Inspect The Testing

Lastly, it’s time for you to verify whether the GEM module troubleshooting is complete. Be sure to inspect any mechanical or electrical issue related to this unit. And, that’s it!

Frequently Asked Questions (FAQs)

Where is ford GEM module located?

Based on older models of ford from 1997 – 2021, the GEM module is located back of the interior fuse box. Also, be sure to check the owner’s manual in order to learn the right spot in an emergency situation.

What does GEM module stand for?

The GEM actually stands for Generic Electronics Module that works like the main controller of power windows, limps, and other parts. Quite similar to BCM aka Body Control Module, it has great ability to shift data rightly to the linked parts.

What is a GEM module in a car?

To put it simply, the GEM module is a computer part, invented by ford in 1994. It helps a lot to make the connected part regulate and operate throughout the truck in the right way.
This module can access the interior parts such as power windows, mirrors, A/C, central locking, and so on. When you switch the ignition to OFF, it takes 10 minutes for the GEM unit to start working.

Overall Thoughts

Still, finding it hard to follow the direction after reading this guide about how to test GEM module? Hope that’s not the case! You see, the GEM module needs to run in the right way to deliver data and signal to its linked component.

And if for any reason, it isn’t able to provide data, then you may need to test out the part. We have given a detailed yet easy-to-understand guide for anyone to simply check or get data related to this subject.

Hope you find this guide informative and try out these methods to test it. We Have To Go Now. See You Soon!

You Can Also Read:

How To Test GEM Module on Ford Trucks – General Info!