[george w]

I'm having a problem with the Traveler trip computer in a 95 Lebaron Convertible I just bought. The VF display isn't lighting up. but I don't think the VF display itself is bad. What's odd is if I physically unplug the unit wait a minute or so and then plug it back in ( with the ign. sw. on ) the VF display will light normally for about 2 seconds and then go off. If I turn the key off and back on it will not light up again until I unplug it, wait a minute or two and then plug it back in. Then the same cycle will repeat, the VF display illuminates normally for a couple of seconds, but only once after it's plugged back in The display read out appears normal when it's lit with full brightness, all characters, etc.
I opened the unit up, cleaned the plug contact surfaces on the PCB and took a look around on the PCB and didn't see anything burned, discolored or out of place. There are about a half dozen small caps on the PCB and they appear OK. No swelling or leaking. There also is a small black disc component that looks like typical MOV one would see in a surge protector or power supply, just smaller in diameter. This looks OK too.

It's as if a cap or something charges up and locks out the display. The instrument lighting bulbs in it work fine as the backlighting for the buttons is as it should be. I assume that there's some form of power supply circuit to provide the power for the VF display itself. It appears that the stored memory / data information is correct as the display reads properly for those couple of seconds it stays lit.

Normally the display should light up as soon as the ign. is turned on. The VF display in the radio works properly and follows the instument dimmer as it should to include the full bright daytime mode with the instrument dimmer setting push past the detent at max. so I think all the right voltages, etc. are getting to the unit through the harness connector plug.

Is there a schematic or service notes ( Photofacts ? ) for these that's available or does anyone know if someone can repair these things ?

 

[Bob Lincoln]

Sure sounds like there is a fault detection and shutdown going on. There may be a resettable fuse (positive tempco resistor) for protection, which could either be doing its job or be faulty. As you know, there are multiple voltages for VF displays - I recall from my old days that there is an AC voltage of, I think, 4 volts on the filament. The grid is higher, can be as much as 28 volts. I found this website that may help, for automotive:

http://hem.passagen.se/communication/vfd.html

 

[ImperialCrown]

In a darkened area, you may see the horizontal filament lines lit a dull orange when the ign switch is on.
There is a dc-to-DC converter that steps the 12 volts up to ~22-28 volts. It may be packaged like an IC. The MOV looking device may be a regulator or protection. Measure the pins when the unit is first turned on and watch for the voltage to drop out after a moment.
The electrolytics were a known common failure, especially after 18 years of service. 'Freeze spray' aerosol may help to locate intermittants.

 

[B10alia]

As for repair, you may be hard pressed to find any information on the unit in the way of schematics. I was trying to cobble together a portable stereo out of an older GM radio, and, as it turns out, electronics companies/divisions really don't like to release schematics of their products or specs on any of the components. In '95, Chrysler still owned Huntsville, but I still doubt you're going to run into a whole lot of information, unless IC or someone else who has a dealer connection can find something for you. Repair will be in the hundreds of dollars, based on initial quotes for a burnt-out Infinity head unit I tried to get fixed a couple of years ago. Fortunately, the AJ-body travelers were decently common, and you may be able to find one on eBay for less than $40 shipped. I bought a (considerably rarer) AA body traveler on there for $20 shipped recently. That would be the route I would go; I'm pretty inept with electronics repair, but that's just my $0.02

 

[ImperialCrown]

These were never serviced at the dealership level other than replacement or exchange. Our regional authorized service depot (United Radio-Syracuse, NY) were the go-to guys for radio, instrument cluster, modules and other automotive electronic repairs.
This service information and many specialized parts are not for the public and are Chrysler-priority only.
If you are good at electronic repairs, you may not need a schematic. Having it plugged into the car connector with the covers off, may allow you some voltage checks. Compare working with not-working voltages.
Delco for instance would go as far as say, releasing a unique 7-pin Delco chip where a standard 6-pin would be available as a generic equivalent in order to keep the parts and repair business their's alone.