Brake and taillights not working...I had a towing package on my 2002 Impreza, the trunk was leaking and the control unit for the trailer got flooded and shorted. Now my brake and taillights are not working, the fuses are good and so are the bulbs. The reverse light and turn signals work. I have completely removed the fried control unit.

As far as I know, your trailer towing package does not include a circuit for trailer braking. These packages normally only supply taillights, brake-lights, and turn signals.
RV sales and service dealerships should be able to help you.
God bless your efforts.

Fuse panel in end of fascia
No. Amp. Function
1 15 Steering wheel lock
2 5 Steering column unit; ignition switch
3 10 Hands-free; cabin CD changer; SID
4 10 Main instrument unit; manual climate control;
automatic climate control (ACC)
5 7.5 Control module in front doors; Park Brake Shift Lock
(automatic transmission)
6 7.5 Brake light switch
7 20 Fascia fuse panel; fuel filler door
8 30 Control module in passenger front door
9 10 Fascia fuse panel
10 30 Trailer socket; electrical socket in storage compartment
between seats
11 15 Data link connection (diagnostics)
12 15 Interior lighting incl. glove compartment
13 30 Accessories
14 20 Radio, sound system I; control panel,
Infotainment System
15 30 Control module in driver's door
16 - -
17 - -
18 7.5 Manual climate control; fan
19 - -
20 7.5 Headlight levelling switch
21 7.5 Hands-free; brake light switch; manual climate
control; clutch pedal switch
22 30 Cigarette lighter
23 40 Cabin fan
24 7.5 Airbag control module
25 - -
26 5 Yaw sensor (cars with ESP)
27 - -


Trunk fuse panel, left-hand side
No. Amp. Function
1-5 MAXI -
6 30 Control module in left rear door
7 30 Control module in right rear door
8 20 Trailer
9 - -
10 30 Left-hand brake light; rear right turn signal; right tail
light; right reversing light; high-mounted brake light;
trailer lights
11 - -
12 - -
13 - -
14 - -
15 15 Seat heating, left seat
16 15 Seat heating, right seat
17 7.5 Autodimming rearview mirror; rain sensor; tire
pressure monitoring
18 15 Sunroof
19 7.5 Telematics (OnStar)
20 7.5 DVD player (navigation system)
21 7.5 Saab Parking Assistance (SPA); control module in
rear doors
22 30 Amplifier, sound system III
23 - -
24 10 Movement sensor; CD changer in trunk (accessory)
25 30 Electrically adjustable driver's seat with memory
26 30 Right-hand stop light; rear left turn signal; left tail
light; rear fog light; left reversing light; license plate
lighting; trunk lighting; trailer lights
27 - -
28 - -
29 - -

Fuse panel in front of battery
No. Amp. Function
1 60
MAXI
Secondary air injection pump (certain models)
2 20 Fuel pump; preheated oxygen sensors (lambda
probe)
3 10 A/C compressor
4 30 Main relay
Relays
1 Secondary air injection pump
2 A/C-compressor
3 Preheated oxygen sensors (lambda probe)
4 Main relay, engine (ECM/EVAP/injectors)

Hello, if you only have taillights on the trailer and no side markers, check your bulbs first. The bright side is used for the Brakes and turn signals and the normal filament is used for the running lights.

If you use a test light you can find the pin on the connector which runs the Running lights. Sometimes the wiring harness will pick up the running lights off of the taillight in the bed of the truck. You would look for a wire going up into the taillight housing from the Trailer plug.

If you are the original owner of the truck there was a small package of Relays and wire ends that came in a plastic bag. It could be stored with the jack. This package had wire color information and instructions for Electric brakes. It also color-coded the Trailer plug-in socket as they use the extra pin holes for the Electric brakes. All the wires are discussed.

If an aftermarket unit was wired in the running light, the wires could be any color. The industry tried to put in a standard, but instructions still say if you don't have one color, its another. That is still vague.

If you don't have a 'plug' for the trailer taillights, then the trailer renter, like Uhaul, sells bulb adapters that hook into the tail brake and light lamps that can power the trailer taillights.

I remember, I had a 1980 Suburban that didn't have a 'compatible' plug, and that's the way we resolved the problem.

Good luck on this towing.

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Trailer Wiring Diagrams 4 Way Systems

4 way flat molded connectors allow basic hookup for three lighting functions; right turn signal / stop light (green), left turn signal / stop light (yellow), taillight / license / side marker (brown) and a ground (white).

4 way tow vehicle side.
4 way trailer side.
5 Way Systems

Same as 4 way system listed above but adds a extra blue wire for brake signal or auxiliary power. Used on pop up camper trailers or utility / boat trailers.
5 way tow vehicle side.
5 way trailer side.
6 Way System, Rectangle Plug 3/4 inch by 1 inch 6 way rectangle connectors right turn signal (green), left turn signal (yellow), taillight (brown), ground (white). The red and blue wire can be used for brake control or auxiliary. Use on a small motorcycle trailer, snowmobile trailer or utility trailer. Can also be used as custom wiring on trailers with 3 light/wire systems. See "Tow Vehicle Taillight Wiring" below.
6 way tow vehicle side.
6 way trailer side.
6 Way Systems, Round Plug

Round 1 1/4" diameter metal connector allows 1 or 2 additional wiring and lighting functions such as back up lights, auxiliary 12v power or electric brakes. Note: The black (sometimes red) 12v and blue electric brakes wire may need to be reversed to suit the trailer. Check with a test light or VOM. Uses: horse trailer, travel trailers, landscaping trailer, car trailer, etc.

6 way tow vehicle side.
6 way trailer side.
7 Way Systems

Round 2" diameter connector allows additional pin for auxiliary 12 volt power or backup lights. Uses: heavy duty landscaping trailer, car trailer, boat trailers, horse trailer, travel trailer, construction trailer, etc. Check with a test light or VOM.

7 way RV flat blade tow vehicle side.
7 way RV flat blade trailer side.

Loosen and pull back the carpeting in the back of the trunk behind the taillights.

Step 2 Remove the plastic wingnuts that secure the taillight to the vehicle's body.

Step 3 Separate the taillights from the vehicle's body, but do not disconnect the wiring.
Installing the Connector

Step 1 Examine the wiring harness on each taillight. There will be a plastic connector on each side that must be separated to insert the wiring harness connector.

Step 2 Thread the trailer wiring connectors through holes in the body behind each taillight. Follow the instructions provided with the connector to determine which connector belongs in which side of the vehicle.

Step 3 Insert the wiring connectors into the vehicle's wiring harness.
Reinstalling the Taillights

Step 1 Push the taillights into position against the body and reinstall the plastic wingnuts that secure them. Be careful not to crush the wiring.

Step 2 Route the trailer wiring underneath the carpeting in the trunk, so that the trailer connector can extend out between the trunk lid and bumper when in use, and be tucked into the trunk when not in use.

Step 3 Reposition the trunk carpet over the taillight housing.

You have got 7 pin trailer connector that was included in the optional trailer tow package. This trailer tow package also includes an electric trailer brake wiring provision that terminates at a connector located on top of the large body harness connection under the instrument panel to the left of the break pedal, as well as an electric trailer brake pigtail harness and an instruction card that are stored in the glove box when the vehicle is shipped from the factory. You will need to add an electric brake controller of your choice that will plug-in to the harness and that will also give you power on your auxiliary circuit.

I asked that becauses of the wiring for the tow setup. If the previous owner had uhaul or one of the other tow companies out there install the wires for the tow package they use a crappy little product that they clamp to the wire and push a pin that cuts the casing and connects the circuit. It also seriously weakens the cables, and lets water in to the wire. Since you have a tow package I'd focus on those wires back there sounds like you may have a short. Those pins do have some wire exposure when installed right and I've seen them bundled and taped on the early 2000's explorers without being individually taped first, which leads to shorts and non working turn signals and brake lights.

Hello you should find a spare plug behind the left hand boot trim near the rear light. You will find all the wiers you need ther.