Questionthe Dash Board does Not Work in My Car..Details (odometer,rpm,fuel,temp above head navigator, and heater controls do not function) the heater is always on, the only way we could even remotly try to fix that is by pulling the blower fuse. all theese problem happened at once, no intermitency or anything jsut stopped worknig one day. was told it was a secondary cpu unti above teh passenger side foot place, but repalce that even checked all the parks on the board ni the unit. Any Ideas?
AnswerHi Jon,
I am a bit limited in specifics about the dash board because I don't have the wiring diagrams for the unit. But there are basically three types of electrical supply that you need to have it working. First, you need battery voltage (12V) to power the illumination lights. Have you carefully examined all the fuses in the junction block (or fuse box) underneath the dash to be certain that none of them is blown or also subtlely cracked somewhere along its internal wire? You might want to see if any of the fuses are labelled as to the instrument panel being their purpose. Similarly under the hood you will find a rectangular box near the battery that has larger fuses and those should be all verified as to their being patent (conducting electricity). Second, you need a return pathway to the negative post of the battery (or 'ground') so that the circuit from the fuse(s) thru the dash and back to the battery is complete. All the items that you described have one or more dedicated ground wires whose predominant color is black (with perhaps a thin stripe of some other color) but in any case any such predominantly black wire needs to be proven to be connected to the metal surface of the body because the body is the ultimate return pathway to the negative post of the battery. Usually all the components in a give area like the dash have a single ground wire where all the individual units splice together and that one ground wire is often bolted to the metal structure of the body on either the right or the left panel called the kick panel. It is the same panel that you described as being the location of the body computer above the side foot place of either the passenger or the driver. So if that one major black ground wire comes loose at its attachment point it will be the same as the fuse(s) for all the devices that are tied into that ground wire lost their power source. So once again, look for a bolt on the kick panel, perhaps near the front door openings on either side where you find the coming together of black wires and a bolt that holds them to the panel. Make sure the surface to which they are bolted is shiney and that the bold is tightly fastened.
Finally, if the lighting of the units is o.k but they just don't function (no data) then there are a pair of wires going to the dash that are twisted around oneanother and these wires are the data bus which carries all the coded information that is needed to make the gauges read, etc. So if that is the problem, rather than totally blanked out units with no illumination, etc., then remove the insturment cluster and look for a pair of twisted wires (colors: violet/brown, white/black) and trace them to their source or splice point to verify that one of the other hasn't been disconnected or damaged which would lose all the signal information for the dash gauges.
I suspect you have lost the ground return to the battery pathway from all the units that are non-functional. So begin there, or with the fuse examination at both places where there are fuses.
Let me know if you find anything of interest.
Roland
