After replacing the wiring harnesses that I botched and replacing the front O2 sensors, my local mechanic advised me that the ECU is not recognizing the sensors. However, he said that with the use of an ohm meter the sensors are fully functional. I was told that the ECU is probably faulty, at which point I purchased one from a vendor on Ebay. This unit did nothing-the car wouldn't start with them flashing it. I purchased another ECU, and the car now starts but dies soon thereafter. Is there some magical code/trick/encantation that needs to be done to the LR ECUs upon installation? Any help would be greatly appreciated.

 

You can't just drop an ECU in and expect it to work. At the very least, in an effort to keep things happy you need a matched EFI ECU and BCU. They must be comparable to what was in your truck otherwise, while they may work, you'll deal with codes. In other words, if you have SAI get a combo from an SAI equipped truck. If you want to avoid issues with the odometer, try to get the instrument cluster from the same truck as well.

I sell the trio from DII's for between $100-150 depending on year, equipment and mileage. That works out to be less than what it would cost to buy just the ECU and take it to the dealer so they can sync it with the rest of your truck. That's really, the only other alternative with these DII's. Matched sets or a trip to the dealer.

 

Is LR the only one that can sync an ECU or can another mechanic do it with software? Is it proprietary? Also, what issues would I encounter with the odometer if the trio wasn't installed?

 

There are some 3rd party products that can resync stuff.

The odometer will blink if it doesn't match what's stored in the BCU.

 

That's why you want to get the three components. The BCU and EFI ECU will work together but they won't match the odometer reading on the original cluster, hence the need to replace that as well.

I think the BCU defaults to whatever mileage reading is higher, BCU or cluster when you don't replace all three at one time.

 

With the proper computer you can sync either the cluster or the BCU to the higher number. Unfortunately you can only go UP. You can also change a setting telling the cluster not to blink on a mismatch, if for example you had a very low mileage truck and you could only get a BCU/ECM from a higher miles, you might not want to sync them at all.

 

Ripping out the dash to put the cluster in seems like way too much work and $$$$, I'm sinking in the money pit with this POS. What the mechanic told me is this-The existing ECU is not recognizing the O2 sensors but when an ohmmeter is used the sensors register. At this point, the mechanic advised me that a new ECU might fix it but these solutions sound more complicated and I don't want to lose miles (I'm at 80K right now). Can anyone offer reasons why the original ECU isn't recognizing the sensors that might save me time and money?

 

Perhaps oil in the connectors? Perhaps a break in the wires between the ecu and the sensors? Perhaps corrosion in the ecu? Trouble shooting this shouldn't be too terribly hard I'd think.

Btw, replacing the cluster is two screws to remove the plastic hood, and maybe four more to hold the cluster in. It's a 10 minute job.

Another option would be a nanocom for $400-$500 and then you could replace just one item and sync the rest. Or maybe you can find someone near you with one.