instrument panel symbols all on =why?

tt330

instrument panel symbols all on while driving

Mr_Shiftright

First thing I'd do is clean all your battery connections, the engine-to-frame ground cable, charge up the battery and checking the charging system voltage output.

thecardoc3

The first thing to do would be to connect a full function scan tool that can communicate with every module on the car and record every trouble code that is displayed, especially any "U" codes which stand for communication.

There is a strategy in place when it comes to turning on a warning lamp. The lamp can be commanded on by the module that controls a given lamp in the event of a failure that has generated a trouble code in that particular module. The instrument cluster can also turn a lamp on all by itself if there is a loss of communication with the module that is responsible for the command state of a lamp. The instrument cluster itself could be suffering a failure which would also result in a given warning lamp. So, before anything else is done, you need to see if the lamp is on because of a trouble code, loss of communication or instrument cluster problem for each lamp that is lit.

You do not want to disconnect the battery and clear memories right now, doing that could cause the loss of valuable data that would help point towards the source of the trouble and make the eventual diagnostics even more difficult than it may already be.

Mr_Shiftright

Good point, although the codes would inevitably come back if the problem re-occurred. But yes, scan for codes first using a top notch scanner, not a code reader.

thecardoc3

Mr_Shiftright said:

although the codes would inevitably come back if the problem re-occurred.

That's not exactly correct because of scripted failure modes, and enabling criteria for codes. Its very likely that codes that might be able to be retrieved right now could be blocked from resetting by other codes that may now set first. That's the kind of information that could get lost by clearing codes now. The nightmare that this causes for shops and techs is that they would get to address what ever codes came back first. Then once those problems are solved, then the other tests are no longer blocked which means that the ones that were hidden from them then get re-generated. People then try to treat that as the tech having done something wrong when that is far from the case.