Hi all, I have an 01 Ranger XLT with a 2.3l i4. I just bought it yesterday morning. My only problem is that the dome light and door chime aren't working. When I picked up the truck, the chime was working fine. I've sprayed the switches and I can hear the relay click under dash when I open the door, but the door ajar light and chime don't come on. However, when I turn the ignition to the run position, the door ajar light comes on, still no dome light. I've swapped out the fuses and relays to no avail. Any help?

 

Welcome to the forum

Does the dome light come on using the switch, i.e. the dimmer wheel all the way up
If not change the bulb and check ground at dome light fixture

The dome light power has two pathways

Fuse 26(cab)----------------Battery Saver Relay-------------------Dimmer switch--------------------Interior light relay-------------------------------Dome light---ground

Fuse 26---------------------Battery Saver Relay-------------------GEM module------------------------Interior light relay-------------------------------Dome light---ground


Interior Lamp Relay is in Relay Box 1(AUX) above gas pedal area, it is a 5 POST relay, when this relay is OFF it passes 12volt from dimmer switch to dome light
When relay is ON, activated by GEM module(door open) it passes 12v to dome light

Fuse 26 powers the dome bulb in either pathway

The GEM also controls battery saver relay, also in relay box 1, this relay should activate, if it was off, when you open the door, then after 20-30minutes with key off and closed doors GEM will turn it OFF cuttng power to all lights in the cab so battery won't be drain by a light that was left on, so it is called the "battery saver" relay, it powers several things in the cab, so fuse 26 is not just for dome light

 

My truck does not have a switch on the dimmer wheel, rather a 3 position switch on the light itself. I did check the battery saver relay, interior light relay, and fuse #26. All good. The chime is working now, but the door ajar light and the dome light itself are not. the switches in the doors are working and I replaced both dome light bulbs.

 

The instrument cluster does a Bulb Test with key on, so all bulbs should light up for the test, its not a systems test just a bulb test, so in this case you know the door ajar light bulb is OK

You are left with the GEM(generic electronic module) as the problem
It is behind the radio
GEM is the Body Computer used in Rangers from 1995 to 2003

Wiring diagram below
The left and right door switches GROUND pins 13 or 14 on the GEM, when that door is open, so closed door = no ground, open door = ground

If GEM sees a ground on 13 or 14 then it should GROUND door ajar light wire. pin 3. black/orange wire to instrument cluster
Most warning lights in the dash get 12volts with key on, and are Grounded to activate them

When GEM "sees" the door switch ground, it should then close interior light relay, sending 12v to the dome light
The interior light relay is a 5 pin relay, so when it is open, dome light SWITCH is getting 12volts thru pin 87A on this relay
When relay is activated, pin 87 sends 12v directly to dome light, by passing the switch, but these types of switches can have a selection to disable dome light full time, so it doesn't come on when door is open

 

Update on this... Previous owner siliconed the connections inside the dome light for some reason. Ended up replacing the whole unit and it works beautifully now.

 

Good work

Thanks for posting the FIX