2003 trailblazer when I had it tested they said the following pump motor circuit is open and the lamp switch circuit

codes are OBDll and are available on line free
https://www.obd-codes.com/p0412

https://repairpal.com/obd-ii-code-p0412-secondary-air-injection-system-switching-valve-a-circuit

If you have trouble in fixing your vehicles, try https://big-manuals.com/products/chevrolet-trailblazer-2002-2009-factory-service-manual . Very helpful

First you need a wiring diagram, free at http://www.bbbind.com/free_tsb.html Then you need a DVOM - digital volt ohm meter to test the circuit . Then if your not familiar with automotive electrical systems testing ,go on youtube an check out Electric Testing Techniques You Need to Know Also having a factory diagnostic trouble shooting chart would also be usefull . You could just start replacing parts , you mite get lucky . The wiper motor is a high fail part , so is the switch ..You could find the fuse is blown ! But fuse's don't usually blow without a reason . Short to ground , low resistance . ( high current flow) Also knowing how they work and what all is involved in making them work.
The Wiper/Washer System consists of the following components:
• Windshield wiper/washer switch
• Windshield wiper motor module
• Windshield wiper motor
• Windshield washer pump motor
• FRT/WPR/WSHR 25A fuse

Wiper/Washer System Operation
The windshield wiper motor module is part of the windshield wiper motor cover and controls wiper motor operation. The windshield wiper motor is a 2 speed motor and is operated at low speed in all modes except HIGH. The accessory voltage supply circuit to the windshield wiper motor assembly is used to operate the wiper motor in all of the low speed modes. The accessory voltage supply circuit to the windshield wiper/washer switch is used to supply the windshield wiper switch signal circuits and the wiper motor high speed circuit.
When the wiper/washer switch is in the LOW position voltage is supplied through a 24K ohm resistor within the switch to the windshield wiper switch signal 2 circuit, and accessory voltage is supplied to the windshield wiper switch signal 1 circuit. The reduced voltage from the wiper switch signal 2 circuit and accessory voltage from the wiper switch signal 1 circuit causes the wiper motor module to close the wiper motor accessory voltage supply circuit to the wiper motor low speed terminal.
Windshield wiper/washer system MIST operation is identical to LOW operation except that the MIST switch is a press and release type. When the wiper switch is moved to the MIST position and released, low speed wiper motor operation is started and will continue until 1 cycle is complete. If the wiper switch is moved to the MIST position and held, the windshield wiper motor will operate in the LOW mode until the switch is released.

Don't the wipers work in any mode ?
1
Did you review the Wiper/Washer System description and operation and perform the necessary inspections?
YES - Go to Step 2
NO - Go to Symptoms - Wiper/Washer Systems
2
Turn ON the ignition , with the engine OFF.
Operate the windshield wiper/washer switch through all the switch positions.
Does the windshield wiper/washer system operate normally?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Turn OFF the ignition.
Disconnect the harness connector of the windshield wiper motor.
Turn the ignition ON, with the engine OFF.
Connect a test lamp from the accessory voltage circuit of the windshield wiper motor to a good ground.
Does the test lamp illuminate?
YES - Go to Step 4
NO - Go to Step 13
4
Connect a test lamp from the accessory voltage circuit to the ground circuit of the windshield wiper motor.
Does the test lamp illuminate?
YES - Go to Step 5
NO - Go to Step 14
5
Connect a test lamp from the signal 2 circuit of the windshield wiper switch to a good ground.
Press the windshield washer switch.
Does the test lamp illuminate?
YES - Go to Step 11
NO - Go to Step 6
Let me know if you make it this far and i will send rest of diagnostic's

The fuse box should be under the hood, passenger side. Try the upper box, middle right side Mine is huge, 30 amp

pump motor circuit ? For what pump ? Fuel ? GM Fuel Pump Relay Testing

Can you move the wiper by hand ? Which does your vehicle have ?
WDA/Z88 The rear wiper is controlled based on an input from the rear wiper/washer portion of the multifunction switch. When closed, the wiper ON and wiper DELAY switches provide a unique voltage signal to the rear window wiper motor indicating the desired speed. Each switch has a unique resistor that drops the voltage to a specified value which is interpreted by the rear window wiper motor as ON or DELAY. The rear wiper motor receives B+ voltage from the I/P fuse block and accessory voltage from the body control module (BCM).
W49 The rear wiper is controlled based on an input from the rear wiper/washer switch. When closed, the wiper ON switch provides a voltage signal to the rear window wiper motor indicating rear wiper operation is requested. The rear wiper motor receives B+ voltage from the I/P fuse block and accessory voltage from the body control module (BCM).
Do you know how to do electrical testing ?
WDA/Z88

1. Ignition OFF, disconnect the harness connector X1 at the multifunction switch.
2. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal 4 and ground.
?‡'
If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to Power Mode Mismatch.

3. Ignition OFF, connect the harness connector at the multifunction switch. Disconnect the harness connector at the rear window wiper motor.
4. Test for less than 20 ohms between the ground circuit terminal B and ground.
?‡'
If greater than the specified range, test the ground circuit for an open/high resistance.

5. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal A and ground.
?‡'
If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.

6. Verify a test lamp illuminates between the ignition circuit terminal E and ground.
?‡'
If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

7. Rear wiper switch in the ON position, test for B+ between the signal circuit terminal D and ground.
?‡'
If less than the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, test or replace the multifunction switch.

8. Rear wiper switch in the DELAY position, test for B+ between the signal circuit terminal D and ground.
?‡'
If less than the specified value, test or replace the multifunction switch.

9. If all circuits test normal, test or replace the rear window wiper motor.

W49

1. Ignition OFF, disconnect the harness connector at the rear wiper switch.
2. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal 6 and ground.
?‡'
If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to Power Mode Mismatch.

3. Ignition OFF, connect the harness connector at the rear wiper switch. Disconnect the harness connector at the rear window wiper motor.
4. Test for less than 20 ohms between the ground circuit terminal B and ground.
?‡'
If greater than the specified range, test the ground circuit for an open/high resistance.

5. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal A and ground.
?‡'
If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.

6. Verify a test lamp illuminates between the ignition circuit terminal E and ground.
?‡'
If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

7. Rear wiper switch in the ON position, verify a test lamp illuminates between the signal circuit terminal D and ground.
?‡'
If the test lamp does not illuminate, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the I/P switch assembly.

8. If all circuits test normal, test or replace the rear window wiper motor.

Component Testing

Do you know how

P0172 states that the "bank 1" side of the engine is running too rich.
Here is a link explaining it in more detail and giving possible causes and solutions.


http://www.obd-codes.com/p0172

The ABS EBCM anti-lock brake module is failing causing problems with the ABS pump running constantly, also will drain your battery.

1. Remove the ABS fuse to prevent ABS motor burn out.
2. You can still drive your vehicle with the module removed.
3. We recommend covering the exposed surface of the hydraulic control unit with aluminum foil to keep out water and dirt.

Common Failures:

• ABS Pump Always Running
• Codes: C0265, C0267, C0268
• Pump Motor Circuit trouble code
• Power Relay trouble code
• Valve Relay Trouble code
• Dump Valves (solenoids) trouble codes
• No Communication
• Intermediate power loss

http://www.myairbags.com/dtc-code-c0265-abs-ebcm-light/

C0237 is related to the rear speed sensor and C0267 is related to the pump motor in the ABS system.

Are you aware of the fact that there are door modules ? Controlled electronically !
Power Window Inoperative - Driver Door
2
Operate the driver power window in the UP and DOWN directions.
Does the driver power window operate properly?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Install a scan tool.
Monitor the Driver Window Status Data parameter in the driver door inputs list.
Does the Driver Window Status Data parameter display an active state?
YES - Go to Step 11
NO - Go to Step 4
4
Monitor the Driver Window Status Data parameter in the driver door module (DDM) inputs list.
Activate the driver power window switch in the up and down positions.
Does the Driver Window Status Data parameter change accordingly?
YES - Go to Step 5
NO - Go to Step 11
5
Connect a test lamp to a good ground.
Backprobe the battery positive voltage circuit at connector C1 cavity D.
Does the test lamp illuminate?
YES - Go to Step 6
NO - Go to Step 13
6
Disconnect the driver power window motor.
Connect a test lamp to a good ground.
Probe the power window motor up control circuit at the power window motor harness connector.
Activate the power window switch to the UP position.
Does the test illuminate?
YES - Go to Step 7
NO - Go to Step 9
7
With the test lamp still connected to a good ground, probe the power window motor down control circuit.
Activate the power window switch to the DOWN position.
Does the test lamp illuminate?
YES - Go to Step 8
NO - Go to Step 10

You probably have a bad door module .