What is the purple wire to my dimmer

so did not check all fuses first? and IS.
can you be more clear, what works and does not work?
electrics failures, we need all that works to
not told does, car drive day or night.? (A#1purpose)
head lamps
brake lamps
parking
turns
radio works
heater dash blower works on high.

gauge back lamps you meant and are part of PARK. +dimmer.

and what does this mean.

dash lights
you mean the cluster waring lamps are dead
like doors open, CEL, brakes, oil, seats belts., etc, be clear .
we are blind here can not see your dash.

buy it used like this or just failed now 30 years later? called out of the blue failed?
name all lamps in the dash that fail there are many
we can not guess them all.
the dash has piles of cluster lamps. (errors) and has background lamps that are DIMMER controlled.
dashboards have many lamps even the shift lever does.

1. car starts and riuns good
2. HL work key on and off, headlamps
3. park ing lamps work
4. dome lamp work (door opens domes glow)
5. cluster error lamps work or not.
6. cluster back ground dimmers work or not.
7. AC panel dead. lamps yes.
8. the car has 2 or more fuse boxs, you do know that riight
9. all facts matter above to fast accurate diagnosis. (I give up)
10. this car had option AUTO lamps , got that?

F13 ,IP box is fuse that can blow. is park feed (HL) to dash
and via the DIMMER. and also glows Illumination on AC panel
THE AC active lamp is a whole other matter.
if the DIMMER works on high but not below that is a BAD dimmer control, for sure)

IP fuse F6 is for AutO Lamps OPTED CARS.


THIS MAKES NO SENSE
I the dimmer switch turn the interior light on still so I'm assuming it's still good
IF DIMMER FAILS FAILS ALL MODES THE FUSE IS BLOWN
IF DIMMER FAILS ONLY OFF HIGH THE DIMMER ITSELF IS BAD.
IT HAS ONLY 2 PINS ON IT.
HOT WITH PARK OR HL ON.
THIS PATH IS DASH AND CLUSTER ILLUMINATION FEED
OR BACKGROUND LAMPS, ONLY, FOR NIGHT DRIVING.

Back lighting or warning lights ? check engine , ABS , air bags , seat belt , oil light etc... ?
Interior Lamps Dimming
The second group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination and incandescent lamps.
• Power window switches
• HVAC control head assembly
• Radio
• The instrument panel cluster (IPC)
When the ignition switch is turned to the ON position, the vacuum fluorescent (VF) display (radio) turns on at maximum brightness. When the park lamps are ON all incandescent back lighting turn ON at the dimming level indicated by the IP dimmer switch. At the same time all vacuum fluorescent (VF) displays dim to match the indicated dimming level. When the headlamp switch is placed in the PARK position, the park lamp supply voltage circuit provides an input to the body control module (BCM). The BCM then supplies voltage to the instrument panel dimmer switch through the instrument panel dimming lamps control circuit. The setting of the instrument panel dimmer switch determines the amount of voltage that the instrument panel dimmer switch supplies to the BCM through the instrument panel dimming lamps low reference circuit. The BCM then sends a pulse width modulated (PWM) voltage to all the interior lamps. All the vacuum florescent (VF) and incandescent back lighting lamps are provided a specific voltage and are then grounded. When the headlight switch is turned to the PARK or HEADLAMP position, all incandescent back lighting turn on at the dimming level indicated by the IP dimmer switch. When the IP dimmer switch is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent back lighting respond from Minimum intensity to maximum brightness in response to the IP dimmer switch.

I would have it checked for DTC'S - diagnostic trouble codes stored in the BCM !
DTC B2624 Display Dimming Input Range/Performance
The body control module (BCM) supplies voltage to the instrument panel dimmer switch through the instrument panel dimmer switch signal circuit. The dimmer switch varies the voltage and returns the new voltage to the BCM through the dimmer switch signal return circuit. The BCM uses this voltage to determine the illumination level of the instrument panel lamps.

DTC B2625 Display Dimming Pulse Width Modulation (PWM) Output Circuit Range/Performance
The body control module (BCM) receives a variable voltage from the instrument panel (I/P) lamp dimmer switch. The BCM uses this signal in order to vary the illumination level of the I/P lamps. The I/P dimming lamps output from the BCM is a pulse width modulated voltage supply used to light the I/P lamps. If a malfunction occurs in the I/P dimming lamps output circuit, this DTC is set.

DTC B2662 Park Lamp Switch Circuit Malfunction
The park lamps are controlled by the turn/headlamp switch. Positive battery voltage is supplied to the switch through the EXT LP fuse. When the turn/headlamp switch is placed in the park or head position, battery voltage is supplied to the park lamps. The body control module (BCM) is also connected to the park lamp circuit to sense whether or not the park lamps turn ON when the low beam or high beam headlamps are turned ON. The BCM also uses the parklamp battery positive voltage to power the instrument panel (I/P) dimmer output circuit. If the BCM senses that the low beam or high beam headlamps are ON and the park lamp input is not active, DTC B2662 sets.
Do the park lamps work ?

the dash has a dimmer, this is dash park lights
and runs all radio back lights.
so if the dial is low, its dark
if the dash cluster glows good the dimmer is ok
and the wire to the radio called, dial

on after market radios its the orange wire. not 12v, its dead.
http://knowledge.sonicelectronix.com/car-audio-and-video/accessories-and-installation/wiring-harness-color-standards/

suzuki uses different colors.
turn on parks, with a voltmeter measure 12vdc at DIAL wire.
at radio.
0v bad, 12v good, if 12v then radio lamps are Blown out.

no other failure> car runs perfect all other electrics perfect.
head lights, parking lights??????

the dash lamps are usually on the park light circuit.
check parking lamps.
check fuses first.

next time say what dash lamps means.
there are a huge number of lamps on the dash
warning lights.
displays
dash parking lamps (back ground glowing for night usage)
called dial lights.
say exactly the lamp that is dead and what it does.

the dash dial lights on all cars have a dimmer control
turn it up,. and bingo the dials glow.

if the dimmer is ok and 12v to lamps the lamps are bad
pull them and replace them.
alldata.com has this.
the FSM for sure, (fact. serv. man)
no schematic ever needed. its just 12v , turn dim to full
see 12vdc there, if there, the lamp is bad.
if not there. the dimmer is bad, or the fuse to it is blown.
check fuses first.
the park circuit on all cars is the most complex (big) of all.
simple but goes all over car, inviting shorts. and blown fuses.
even trailer wiring hacks. ever look at your harnesses.
if just dash is dead.its in the dash.

there are many lights,
idiot lamps (charge , oil, CEL)
and parking dimmer lamps.
each as a different use and meaning , key , running or just with parking lamps on,

if just the park lamps all dead, turn the dimmer to max.

the dash dimmer turned down? i guess you mean parking lights and dash dimmer, is dead in clock. but is it dead in the whole dash?
if the dash is dimming and the clock dim lamp is dead (park) then its bad. (check fuses in all cases first)

All go out at once, first check fuses,then dimmer switch for dash lights, finally headlight switch. To check dimmer switch, pull connection off back, on harness with test light and headlight switch activated, 1 of the leads should have power, if so, use ohm meter on dimmer to make sure it has reading between 0 and some value, if no value, open, dimmer is bad, if there wasn't power then check headlight switch, there should be heavier gauge wire that powers switch and 1 for output to hi/lo switch, smaller gauge wires for tail lamps, dash lights, license plate lamps, parking lights. The color wires from dimmer would correspond to the same colored wires on headlamp switch, probe that connection on headlamp switch with switch engaged and see if you have power, if not replace switch, if so, check wire from switch to dimmer.Now if the lights slowly went from bright one day, to less bright some other day, to not working, then the bulbs are bad... good luck...

Hello !

If the lights in the dash do not work, do the parking lamps work?

If so, the fuse is good, as they both share the same fuse.

What you have, is possibly a malfunctioning dashboard dimmer switch; the round knob on the lower side of the dash. It may be turned down, or it has internally failed. To check it, simply use a 12 volt test lamp, or a volt-meter. Unplug the dimmer switch, and see if there is 12 volts in one of the two wires at the connector. If you have power, and the stwich is turned up, you have a bad dimmer switch.