Hi, my brother has a 2009 F150 with the 5.4L with about 110,000 miles. His airbag and ABS lights came on recently and so he took the truck into a shop. They diagnosed it as a faulty ECU which would need to be replaced at the dealership for about $1400. I would like to try and help him somehow. How can this be tested to verify the ECU is faulty or not? Is this something that can be replaced at home?

 

If the lights are on there should be some codes stored. Do you know the codes?

 

He is bringing the truck over either today or tomorrow and I will see if/what codes are showing. Is it safe to open the ECU and check for any shorts? Would this possible damage the ECU (I don't know if it is a sealed unit or something)

 

You can't program that at home, I don't believe. Would need some sort of service manual to really check it out. But. checking the wiring would certainly be part of a diagnostic, as would checking codes. IDK about 2009, but I would definitely be suspect of a PCM diagnosis for airbag light in a 2013. The computer that is common to both these lights is the cluster.

 

Well, that's what I thought, but I have found an online ECU that is pre-programmed and seems to be a plug and play item

 

The 11 years I worked at a Ford dealer I can count on one finger how many PCM's I had to replace because they went bad for no other reason like a lightning strike or flood. Highly unlikely but no way to know for sure without putting hands and diag equipment on.

That year model had separate computers for ABS and SRS (air bag) separate from each other and separate from the main PCM.
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I did not know it had separate computers for those modules. So sounds like the shop was just trying to rip him off?
I am going to look at the truck tomorrow and put my OBD2 tool on it and see what I can find, but I am no expert especially in electronic side of vehicles

 

Where do you suggest I start looking knowing that both of these lights ABS and SRS came on at the same time with no obvious cause?

 

Start by retrieving codes. The ABS and SRS systems are completely separate except they both communicate over a multiplexed CAN.
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Start with the codes. It will narrow the playing field tremendously. If you don't have Forscan, I highly recommend it for DIY troubleshooting and diagnosis. Its free, however you will need to buy a dongle (~$30 on Amazon) and have access to a windows laptop.

ABS modules are common failure points on these trucks, buts its all speculation without the code(s). A bad wheel speed sensor, or even a grossly odd size tire will trigger a ABS light as well. Get the codes. There are a lot of good folks here on the forum that will help you.