An immobilizer is an electronic device fitted to an automobile which prevents the engine from running unless the correct key is present. This prevents the car from being hot wired after entry has been achieved. The microcircuit inside the key is activated by a small electromagnetic field which induces current to flow inside the key body, which in turn broadcasts a unique binary code which is read by the automobile’s Engine Control Module (ECM). When the ECM determines that the coded key is both current and valid, the ECM activates the fuel-injection sequence. The immobilizer function of the Nissan Vehicle Immobilizer System (NVIS) or Nissan Anti-Theft System (NATS) consists of the following: – NATS ignition key – NATS antenna amp. Located in the ignition key – Body control module (BCM) or (IMMU) – Engine Control Module (ECM) – Security indicator lamp.

Hi all I'm new to this and I'm also new to Cadillac ownership. I bought a very good 1996 Eldorado Florida car no rust and only 130000 kms.I like the car very much, I really like the lines. I am however becoming disenchanted rapidly. I've owned the car for about 5 months and already have had to replace alt. A/c compressor among other things then the prindl started flashing and anti-theft message came up, I tried a veriety of things to no avail then took it to a small shop that had it for about a month then took it to the dealership for proper diag. They said all things pointed to the pcm, replaced it and all was well for about 2 wks when all of the sudden the prindl started to flash and anti theft message appeared as well as my a/c control unit when black.

P1610 loss of pzm serial data. Oct 19, 2005OFFICIAL list of fault codes ODBII code list DIY: Do It Yourself. P1610 loss of pzm serial data. More than just a list of GMC Check Engine Light Codes! Our resources can help you fix your check engine light now! Informative articles, technician advice, component. Diagnostic Information and Procedures - DTC P1610 Loss of PZM Serial Data - For 1998 Cadillac Seville. This procedure is found in the Seville (VIN K) Service Manual. It is located in the section: Engine / Engine Controls - 4.0L and 4.6L / Diagnostic Information and Procedures. Service manuals, electrical schematics and.

Car started and ran and for some reason I turned on my headlights by pulling out the knob and low and behold the prindl stopped flashing and message disappeared and the a/c control unit came back to life, so every time I turn the lights off everything gose nuts and back to normal with headlights turned on manually. Has anyone heard of this and my question is, is the headlight switch assembly tied into the anti-theft some how. Any assistance would be gratefull, I'd really like to like my car again and be able to trust it THANKS MIKE. NO, is not tied into it, but may share a common ground! There are 2 reasons the PRND321 will flash: 1) PRND321 flashing on IPC while the shifter is NOT in Park (you just shifted into a gear) it means the shifter is in a intermediary position between gears. 2) PRND321 flashing while the shifter is in park (say you never touched it) it means IPC has no data communication with the rest of the car modules. It will also post every single conceivable message on the display plus most of the warning lights will be on (not the case for 1) as shown in this picture of a IPC powered on a bench (no data communication).

East Asian Languages Installation Files For Canon. You have to pay attention and tell which of the 2 situations apply to you. Also you need to pull your codes. (no need of a scanner, the car has one integrated). Post the codes AND the definitions.

Pay special attention to the IPC 'U' codes. The PCM was changed for no reason, will not cause the issue you mentioned. Your car being a '96 officially is OBDII, unfortunately is not fully OBDII, you may find yourself using OBDI code definitions as well. I HATE '96 cars, are so difficult to diagnose with the confusing codes they have. Off course a miss aligned cable may trigger situation 1 even with the shifter (in what you believe to be) P, so again pay attention to the details. I can't find all the code (sorry not enough time) as I mentioned your car is OBDII (almost) so is a bit of a search to figure out what are the codes (BODI or OBDII). But form what I see you are missing the voltage to the IPC, one code is about the keep alive memory (means IPC lost power), one is about terminal L on the alternator, one is key validation.

A bad ground, a low battery voltage or a bad connection at the IPC connector could cause all these. Please come back with all the code definitions I don't care what's current and what's history, in your case are EQUALY important. Here is an update, I've been thinking about all those codes and came to the conclusion that most of the codes are probably related to the problem I had with the anti-theft issue which caused no start,dead battery, ipc removal and replace and finally pcm replacement.

So I made a list of the codes and then proceeded to clear them, driven the car for a day and the codes that reappear are pc 1605 hvac loss of serial data and pz 2255. The problem that still exists is when I start the car the a/c control head is dead as soon as I put the car into gear the prndl flashes and as soon as I turn on the headlights the prndl stops flashing and goes back to normal and the a/c control; head comes to life.

I'd like to thank everyone for their input mike. DON'T replace IPC and PZM, 99% is a wiring issue not a module issue. Scissor Sisters Ta Dah Rarlab more. Sure is easy to replace a module, just unhook the connectors, and this is why people go for it as not most know how to check wires. Replacing the IPC requires the IPC VIN RPOs and SIR registries to be programmed matching your car. The mileage must also be programmed (this is legal matter).

Replacing the IPC requires reflashing it. When either one of these 2 modules is replaced the password relearn procedure must be performed (takes 30 minutes or 10 having a TechII). Then you have to worry about VAT, there are 10 VAT values and you have 1 in 10 chances the replacement IPC VAT will match the original. This means you need to get new ignition keys with matching VAT. The fact you have Theftlock issues YET AGAIN suggest me you have WIRING issues. I would suspect maybe water damages (corrosion) in the IPC connector.

Again I have to point again to provide the definition for the codes, I only try to help you so far, at some point I will give up. VBulletin Security provided by - Copyright © 2018 DragonByte Technologies Ltd.

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