swapping out the ECU

[nikan]

Hi, so I think I need to swap out the ECU on my sentra 02 gxe. What happened was, the car just shut itself off at a traffic light and refused to start again. I towed it to the mechanic and he could not get his scanner to communicate with the car so he thought that the ECU was fried or something. He did not seem to know about the electrical stuff too much, so I guess I am on my own to try to get my car out of there.

I mean there are probably other issues with this car, but we need a functional ECU to start with.

I can buy a used ECU with the same part number off ebay for around $100. I believe with an older car like mine, it is just plug-and-play without any needs for reprogramming/reflashing the ECU. I heard the only time reprogramming is needed is if there is an immobilizer which I do not believe my car has.

I was wondering if any of you are more familiar with this topic and can give me a few pointers on what to expect when I swap out the ECU. I hope to get a few more years out of this car as it has low mileage and I have been taking care of it as much as I could. Many thanks and have a blessed year to all!

[B13_Red]

How about checking the relay/circuit that powers the ECU? No OBDII comm's + no start= dead alternator/battery...?

[nikan]

How about checking the relay/circuit that powers the ECU? No OBDII comm's + no start= dead alternator/battery...?

thanks for your reply. The mechanic said he checked all that and saw no problems. Which is strange because as far as I know the ECU just doesn't go bad by itself.

i'm surprised as I can't find many discussion about people swapping out their ECUs. I heard that it would even change your VIN number but do not know what problems that may cause.

[B13_Red]

Tis rare but not unheard of (ECU fail). Could a pin/contact on the OBDII port connector be open? Maybe the master relay powering the ECU a problem, or that ECU power-up circuit in general?

[nikan]

swapped out the ECU and it is running well now. But we still do not know what makes the old ECU fail in the first place. Guess we just hope and pray that it won't happen again.

[Supercourse]

Bravo for getting it going again for a modest price.

Had a similar problem with an '07 Sentra only it happened after re-connecting the battery after a 4-week idle period. Battery had been charged up before re-connecting.

Seems like an unstable voltage supply from the 10 year-old battery killed the ECU. Had to get a reman. one through the dealer at about 10 times what you paid. Ouch.

But as later model with immobilizer it did require programming to get going again.