Immobilizer question Topic is solved

[subzerocarfanatic]

ABS-0093 definition... control module communication, no load signal.
Cause... fault in engine management system.
This narrows it down some but I am a bit puzzled. So is the ECM not sending a signal to the ETM when the ignition is turned on to allow the ETS check lamp to come on so it starts because of a software issue, and if so how did I arrive at this problem? I have no idea! Is it ignition related?? I do not think so but I am not certain. I need some more help. How will I know for certain if it is a software issue related to the ECM ?

[subzerocarfanatic]

If there is an issue with the ECM why is the ECM control module not lit of orange or yellow like the other 2 modules are that have DTCodes? More reading I guess....

[subzerocarfanatic]

Anyone know where I can find a wiring diagram, or have an image to share please of the engine / relay box area wiring so i can try to trace and maybe get lucky and find something, in case it is not software related.

[abscate]

We don’t host them here by legal agreement with Volvo NA but they are public on the web.

Search for document TP3938202 in the Google Clouds..

[subzerocarfanatic]

It should be either 0 Volts or within 0.1 V of the battery voltage across the terminals

I wonder why the 1st fuse ( the one i pull to start each time) which is the ignition switch contact system fuse, has battery voltage even when the key is off, the other 4 fuses inline with it do not have voltage unless key is on. Is it always supposed to be hot?

[abscate]

It should be either 0 Volts or within 0.1 V of the battery voltage across the terminals

I wonder why the 1st fuse ( the one i pull to start each time) which is the ignition switch contact system fuse, has battery voltage even when the key is off, the other 4 fuses inline with it do not have voltage unless key is on. Is it always supposed to be hot?

Terminal 15 is always HOT in DIN code and many circuits are Terminal 15 sourced. The ECU is terminal 15 so it holds the adaptive parameters and ECM codes in memory - unplugging it resets these.

Terminal 30 is key position II HOT , the big electrical loads

[subzerocarfanatic]

This isn’t an antenna ring problem. Pulling that fuse is probably doing an ECU reset which helps the starting sequence.

If cranking is inhibited on a 1999 or 2000 car, your light control module , 2/76 is not grounding your starter relay. It does this under microprocessor control , not a simple thing to diagnose.

If it cranks, starts, stalls…that’s a bad key signal.

abscate, could a software related issue cause the car to only start if the 15 AMP ignition switch contact system fuse is removed then reinstalled as I mentioned? I found with the AUTEL MaxiPro MP808 scanner that it has a few DTC , one being DIM-000D communication, ECM; Internal fault. I looked it up and it mentions something about ECM software. I do not understand why the software would have issues!
You mentioned the ECM earlier, so maybe pulling that ignition fuse each time then re-installing it is resetting a signal to the ECM so it lets it start, I need to figure out what is causing it and why!! Could a software issue cause this, if so what would cause the software to have an issue and if so why would the car run at all even with me resetting it by pulling and reinstalling the fuse?

abscate, where in the vehicle is this 2/76 located, is it a relay, a shared circuit or module or what? I have been trying to locate it on the wiring diagram and have not found it yet, except maybe one, it looks like a wire coming from the ECU to the OBDII plug, is this what you were referring to for me to start with my check in tracing for a short etc. ? Thank you for your help.

[abscate]

2/76 s the lock
control module. Its a white plastic box clipped to the frame under the dash - you need to remove the kick plate on the driver side to see it. It has two green plugs (A and B) and a printed circuit board inside.

Troubleshooting that board is nasty.

Its primary function is to control the interior lights, which are quite complicated.If you trace the ground side of the starter relay, though you will find terminal 85 connects to a B pin on the 2/76 light module.

Cranking is initiated by and ECU signal to the 2/76 ligth control module which grounds the starter relay.

Here is a thread on 2/76; it is Dante's Inferno..

viewtopic.php?f=1&t=88623&hilit=evita+l ... leshooting

[subzerocarfanatic]

2/76 s the lock
control module. Its a white plastic box clipped to the frame under the dash - you need to remove the kick plate on the driver side to see it. It has two green plugs (A and B) and a printed circuit board inside.

Troubleshooting that board is nasty.

Its primary function is to control the interior lights, which are quite complicated.If you trace the ground side of the starter relay, though you will find terminal 85 connects to a B pin on the 2/76 light module.

Cranking is initiated by and ECU signal to the 2/76 ligth control module which grounds the starter relay.

Here is a thread on 2/76; it is Dante's Inferno..

viewtopic.php?f=1&t=88623&hilit=evita+l ... leshooting

Not sure if the interior passenger side overhead sun visor lamp not working has anything to do with a short related to that, or the passenger side rear seat window control switch not working properly, it has to be rolled down with the rear passenger window switch but can only be rolled up with the drivers master window control switch, yet the drivers master window controls wont roll that rear passenger window down, only up. Kind of weird. All other interior lights and switches work to best of my knowledge. The climate control always has a green and amber color light on even when it is off and not in use but that is it.

[RickHaleParker]

Search for document TP3938202 in the Google Clouds..

TP3938202 is for the 1999 C70. TP3943202 is for the 2000 - 2004 C70.