Replacement ECU Do I need to program the new ECU or just remove the damaged one and put the new one?

It's possible that the ECU (Engine Control Unit) may have been damaged when you switched the battery terminals on your Citroen Xsara Picasso, but it's also possible that the issue is related to the configuration of the ECU.
The P1613 error code typically indicates a fault in the configuration of the ECU, which can be caused by a variety of factors, including a dead battery, a faulty ECU, or improper programming.
Before replacing the ECU, it's a good idea to try resetting the ECU to its default settings. Here are the steps to follow:

1. Disconnect the battery and wait for at least 30 minutes.
2. Reconnect the battery and turn on the ignition.
3. Wait for a few minutes before starting the engine.

If resetting the ECU does not resolve the issue, then it's possible that the ECU has been damaged and may need to be replaced. However, it's important to have the issue diagnosed by a qualified mechanic before replacing the ECU, as there may be other factors that are contributing to the problem.
If you do need to replace the ECU, it's important to ensure that the new ECU is properly programmed for your specific vehicle, as failure to do so can cause further issues with the vehicle's performance. A qualified mechanic or dealership should be able to assist with the replacement and programming of the ECU.

Well, ya might wanna do the Math; the money you spent for the New ECU, Plus reprogramming, Plus a new Valve timing belt, Plus other issues which are not evident because, the Car isn't running... I'm pretty sure we've past the Car's value.
https://www.nadaguides.com/Cars/1998/Hyundai/Tiburon/2-Door-Coupe/Values
However,
You need the Key that is for that ECU
OR
A *new key needs to be programed into the ECU
Also, since the ECU has been unplugged for x amount of time; The ECU needs to be programed, Now
*Your OLD Key may not be readable.

For do it yourselfers; When replacing PCM/ECUs,
Body PCMs, Programable Fuel injection, Instruments and such... with used parts
Recommend; getting access to a complete RUNNING donner Car at Pick and Pull or Pull Part or...


Sorry, I'd like to help but, Seems to me a Dealer only problem at this point.

remove ecu and install new ecu, then take it down to dealership to get it programmed. or just take it to a dealership to have them do it.

If you dont know anything about the ECU.... I would take it to the dealer.... I had the same problem....ECU had to be replaced....they know what they're doing. I was out of there in a couple hours.

if it is just the fuel problem with the ecu, replace the chip in side the ecu from the new one you got as then you dont need to re program it then. the fuel chip and control is inside the ecu. you used to be able to get the chips for them and program the codes onto them. should be clip in type chips. if its soldered type as there are 2 types of ecu boards with same part number. you will need to un solder the chip.

Electronic Control Unit, An engine control unit (ECU), most commonly called the powertrain control module (PCM), is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure the optimum running. It does this by reading values from a multitude of sensors within the engine bay, interpreting the data using multidimensional performance maps (called Look-up tables), and adjusting the engine actuators accordingly.

Automotive ECU is to convert stored procedures chip in simple, replace the programmed chip, as long as open the backplane of the ECU and unplug the original chip and then put the new chip , as some older E-ROM chip only can write just one time, every time you modify the program you must turn the program of original chip into a blank chip and then replace the original chip. If you want to have a program modified by yourself, you need a ecu programmer.

You need to have the keys programmed to the new ECU. WIthout doing this, everything except the fuel pump will operate.

Def'.. sounds like there is a problem with the ecu holding data, had the same problem with a Skooby. If you replace the ECU then ensure you get the correct data codes which are on the side! not sure if your immobiliser is coded to the ignition key! if they are then you ill need to have the keys programmed to the new ecu. it's going to cost a lot!

Its an easy job! Disconnect the battery first! That's very importand! Then disconnect the wiring pack from the ECU. Some models are equipt with snap-systems, other with a screw-system to remove the wiring connector from the ECU. If done, there are three or four screws that hold the ECU in place with the body. Remove the screws and you hold the ECU in your hands. To buy a new or rebuilt ECU, reffer to the numbers shown on the label at your Wranglers ECU in combination with the V.I.N. To connect the new ECU with the wiring pack, be careful with the connector! You need to put him in the right position to connect with the ECU. Do it slow and make sure the connector fits to all points. Otherwise you'll bake some contacts inside the connector.

PS...ignore person who answered...he is an intruder, and not part of the "team" !!!