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Knock sensor low voltage issue

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New to the EB world. Just bought one and running into a couple of issues. First is code P0332 i believe is what it is. Low voltage on knock sensor bank 2. Previous stated he replaced twice, and it just comes back. It's easy to clear it with the programmer but still an inconvenience. Believe it's going to be a wiring issue. Has anyone had any failure points on the harness that I can look into before I pull everything and start tearing it apart? Second. Key Fobs, keys will start the car but none of the outside functions work i.e.. unlock, remote start, trunk pop. I found that the rearmost receiver under the panel under the back window had been unplugged. Plugged it in but still no help. Yes, the batteries have been switched, and fuse been checked. Since that receiver was unplugged would it need to do a relearn before the keys became operational again? Lastly the driver mirror just doesn't work. Light doesn't come on, doesn't move. Fuse has been checked. Any common issues I need to know that I can check before I take it off? Thanks for any help.
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Paddles

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Are the key fobs OEM?
 

Skye

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Second. Key Fobs, keys will start the car but none of the outside functions work i.e.. unlock, remote start, trunk pop. I found that the rearmost receiver under the panel under the back window had been unplugged. Plugged it in but still no help. Yes, the batteries have been switched, and fuse been checked. Since that receiver was unplugged would it need to do a relearn before the keys became operational again?
New to you Eco. Curious of any of the previous vehicle history (locations, maintenance, modifications, how purchased, etc.).

The Radio Transceiver Module (RTM) being unplugged...that is weird, and, something of a tell.

Standing outside the car, fob in-hand, fob buttons have no effect. Check.

Standing outside the car, fob in-hand, can you unlock/lock the door by touch?

Are the fobs the factory units? Have they ever worked as expected? You have two, yes?

Driving the car, does the Tire Pressure Monitoring System (TPMS) display the tire data? If the TPMS data displays, that's a good sign: the RTM is connected and transferring data to the Body Control Module (BCM). If not, could be the RTM or connections.

The RTM is the receiver for both the key fob and the TPMS sensors in the wheels. The RTM is physically attached to the car's networks and logically connects to the BCM.

If...If the RTM has been replaced, it needs to be confirmed it's the correct one. For a 6G car, it should operate at 315 MHz (the TPMS freq). Newer (7G) and EU models operate at 433 MHz. Others still (large trucks, SUVs) are dual frequency or operate at 868 MHz and other frequencies.

If TPMS data is being seen, it confirms the right type of RTM, a good RTM and connectivity. If TPMS information is not registering, it could be problems with any one of those topics.

To support the fob and access key, the RTM must be programmed with the car's VIN and vehicle data. The RTM requires knowledge of the car and fob. Studying on-line, if you have FORScan, you might be able to program the RTM yourself. You should at least be able to query the module, confirm connectivity and frequency. If not, a trip to the dealer would be required. You can check with locksmiths. While a locksmith can program fobs, IDK if they'd have the insight to program an RTM.

In the door panels, deck lid area and the interior center console are inductive coupling units; these present electromagnetic fields. There's a mini transformer associated with the key in the fob. Energized by these fields, the fob becomes powered and capable of talking to the immobilizer in the steering column. With this minimalist communication, the car will start and can be driven.

Why the RTM was disconnected...I can think of all kinds of reasons why someone previously disconnected it, from the funny to repair attempts to WTF. The modules and wiring do fail. Occasionally. RTM and associated issues are not common to the 6G, but they happen.

With the issues presented and the recent purchase, I'm curious of the car's history.
 
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From what I understood the owner before the one I bought it from lived in the Dallas area and was worried about someone stealing it. I do not have forscan atm unfortunately. I have no reason to believe the keys aren't oem but dk how to tell. Ive already got a date with the dealer was just hoping there may be an easier fix so I wouldn't have to pay their prices. And no, none of the "remote" functions work. Only thing that works is putting the key in the backup slot in the cupholder and starting it.
 

Skye

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lived in the Dallas area and was worried about someone stealing it.
So, that explains the disconnect. Kind of good in a way. Removes a lot of doubt.

The RTM is simply a programmable module. Being solid state, I'd think it wouldn't lose anything being disconnected? 🤷‍♀️🤷‍♂️ But we also don't know what else they did. He might have zero'd the unit out, then disconnected it.

Glad to see the appointment with the dealer. They'll hock up and confirm connectivity. Programming the RTM shouldn't be that big of an issue.

I took the physical key from my fob. Looking at the fob itself, there are some number references. One begins with "JR3T" and is followed by other numbers. This number immediately displayed as a Ford fob, often a Mustang fob, when googling. The base also has the Mustang logo on the back; IDK when Ford started doing that. No other Ford logos on the fob.

I'd like to think with the RTM re-programmed, you'll be GTG. With that, you might want to update the title of your thread, referencing the low voltage event on the knock sensor. Some Members might have some experience with that.

Good Luck. Welcome to the Forums. :fistbump:
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