Pioneer DEH-S5120BT Audio Receiver Wiring Diagram
Complete diagram
Every cable and connector on the unit and where each one goes.
Terminals and components · 17
- Constant 12 V
- Switched 12 V
- Ground
- System remote
- Illumination and preamp
- Speakers
- AUX input
- Connectors
- Antenna and devices
Caution
Do not let the lead wind around the steering column or shift lever; secure it with clamps.
Hubs
Connection through a USB hub is not supported.
Settings
Turn the AUX setting on in the menu to use it.
Separate screws
The power amp ground and this unit's ground go to the body with different screws. A loose screw can cause smoke, fire or malfunction.
Caution
Do not run it to the battery through the hole into the engine compartment.
Fuse
The rear of the unit has a 10 A fuse: replace it only with one of the same rating.
No ACC position
If the ignition switch has no ACC position, connect it to a terminal that detects the key; otherwise the battery will drain.
Never to a power terminal
Never connect it to the power terminal of an amp or auto antenna: it may drain the battery or cause a malfunction.
Glass antenna
If the vehicle has a glass antenna, connect it to the antenna booster power supply terminal.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Subwoofer
The subwoofer output is monaural.
Speaker leads
The eight speaker leads with their polarity, with four speakers or with a subwoofer on the rear leads.
Terminals and components · 4
- Speakers
- Unused
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Caution
Tape any unused speaker leads. With a two-speaker system, do not connect anything to the spare leads.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Setting
With a subwoofer on the rear leads, set the rear output to subwoofer (SW) in the menu.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
Setting
With a subwoofer on the rear leads, set the rear output to subwoofer (SW) in the menu.
Negative leads
Do not ground the speaker negative lead or band it together with other speakers' negatives.
2 Ω subwoofer
A 2 Ω subwoofer (or two 4 Ω subwoofers in parallel) goes only to the violet and violet/black leads and must be rated over 70 W. Connect nothing to the green and green/black leads.
Setting
With a subwoofer on the rear leads, set the rear output to subwoofer (SW) in the menu.
2 Ω subwoofer
A 2 Ω subwoofer (or two 4 Ω subwoofers in parallel) goes only to the violet and violet/black leads and must be rated over 70 W. Connect nothing to the green and green/black leads.
Setting
With a subwoofer on the rear leads, set the rear output to subwoofer (SW) in the menu.
External power amp
RCA outputs to the amplifiers and the lead that turns them on.
Terminals and components · 5
- Preamp
- System remote
- Amplifier
Amp turn-on
Connect it to the system remote terminal of each amplifier.
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Plugs
L = left, R = right; connect with RCA cables (sold separately).
Subwoofer
The subwoofer output is monaural.
About This Diagram
These diagrams are redrawn from page 3 of the Pioneer DEH-S5120BT Audio Receiver manual, and we offer them completely free and in English. We have also categorized it in the Car Audio & Stereo (Automotive) section on Diagramverse, and it has been rated by 1 user with an average rating of 5.0. If you have any specific questions about the Pioneer DEH-S5120BT Audio Receiver Wiring Diagram, we suggest checking the Frequently Asked Questions (FAQs) section.
Printable Pioneer DEH-S5120BT Wiring Diagrams
Wiring Instructions
Before you start
The Pioneer DEH-S5120BT is designed for 12 V, negative-ground vehicles only. It runs on 14.4 V DC (10.8 V to 15.1 V allowable), draws up to 10.0 A, and is protected by a 10 A fuse on the power cord. Pioneer recommends professional installation. Hire an installer if you are not comfortable working with vehicle wiring, or if the job means drilling holes or modifying the vehicle.
- Tools: trim removal tools, screwdrivers, a digital multimeter, crimp tool and connectors, insulating tape and cable clamps.
- Harness: use a vehicle-specific harness adapter if your car has one. Do not shorten the unit's cables, and never cut into the power cable to feed other devices, because its current capacity is limited.
- Speakers: each speaker must be rated over 50 W and 4 to 8 Ω. Never use 1 to 3 Ω speakers on the four channels. A 2 Ω subwoofer on the rear channel must be rated over 70 W.
- Power isolation: disconnect the battery negative terminal before you touch any wiring.
Choose the right diagram
Use the Complete tab for an overview. On the Speakers tab, pick the variant that matches your system:
- Four speakers: four full-range speakers.
- 4 Ω subwoofers: 4 Ω subwoofers on the rear leads, with no amplifier.
- 2 Ω subwoofer: one 2 Ω subwoofer on the violet leads only.
- Two 4 Ω in parallel: two 4 Ω subwoofers sharing the violet leads.
Use the Power amp tab if you add external amplifiers on the RCA outputs.
Step-by-step wiring
- With the battery negative disconnected, remove the old radio and identify the vehicle wires: constant 12 V, ignition-switched 12 V, illumination, the speaker pairs and the antenna. If you are not sure about a wire, check it with a meter before you disconnect the battery, then label it.
- Connect the Black chassis ground first, to a clean, paint-free metal point on the body. If you install a power amp, give its ground its own screw. Never share one screw between devices.
- Connect Yellow to the constant 12 V supply terminal. Do not run it through the firewall straight to the battery.
- Connect Red to the terminal controlled by the ignition switch. If your ignition switch has no ACC position, red must go to a terminal that detects ignition-key operation, or the unit will drain the battery.
- Connect the speaker pairs, observing polarity: FL white + and white/black −, FR gray + and gray/black −, RL green + and green/black −, RR violet + and violet/black −. Never connect a negative lead to ground, and never join the negative leads of several speakers together.
- For a 2 Ω load, whether one 2 Ω subwoofer or two 4 Ω subwoofers in parallel, use only violet and violet/black. Tape the unused green and green/black leads.
- Connect Orange/white to the car's illumination signal so the display dims with the lights.
- If you have amplifiers or a power antenna, connect Blue/white to the amp's system remote terminal or the auto-antenna relay control terminal (300 mA max). If the car has a glass antenna, connect blue/white to the antenna booster power supply terminal instead. Never connect blue/white to an amplifier's or antenna's power terminal.
- Connect RCA cables from FRONT OUT, REAR OUT and SUB OUT to your amplifiers.
- Plug in the antenna at ANT. Route the MIC lead to the sun visor or steering column, keeping it clear of the steering column and shift lever. Connect a steering-wheel adapter to REMOTE if you use one.
- Cover every unused lead end with insulating tape. Secure the wiring with clamps, and keep it away from seat rails, the shift lever and heater outlets. Wrap tape wherever a wire touches metal.
- Mount the unit at less than 60° from horizontal and leave ample space behind it for heat to escape. Make sure loose cables do not block the vents.
Testing and start-up
- Before final assembly, reconnect the battery and measure at the harness. Yellow should read about 12 V at all times. Red should read 12 V only with the key in ACC or ON.
- Remove the front panel and press RESET with a pointed tool longer than 8 mm. Do this once before you use the unit for the first time.
- Turn the ignition ON. The setup menu appears; set the language and clock.
- In the INITIAL settings, set REAR-SP: FUL for full-range rear speakers, or SW for a subwoofer wired directly to the rear leads. Then set SP-P/O MODE to match what is on the RCA outputs. Set SUBWOOFER to ON in the AUDIO settings if you use one.
- Start at low volume. Use FADER and BALANCE to confirm that each speaker plays from its correct position. With the unit on, blue/white should read about 12 V, and your amplifiers or antenna should switch on.
Safety notes
- Car batteries can deliver very high short-circuit current. A loose ground screw or a bare lead touching metal can cause smoke or fire.
- Replace a fuse only with one of the same rating, 10 A on this unit's power cord.
- Keep the unit dry. Liquids can cause shock, overheating or smoke.
- Leaving Bluetooth on standby while the engine is off can drain the battery.
Troubleshooting
| Symptom | Probable Cause | What to Check |
|---|---|---|
| The radio is completely dead, with no display at all | No power on yellow or red, a poor black ground, or a blown 10 A fuse | With the key in ACC, measure about 12 V from yellow and from red to chassis. Check the 10 A fuse on the power cord. Make sure the black ground is on bare, paint-free metal and the screw is tight. |
| It forgets the clock and presets every time I turn the car off | Yellow and red are swapped, or yellow is on a switched circuit | Key off: yellow must still read about 12 V. Swap yellow and red, or move yellow to a constant 12 V source. |
| My battery goes flat overnight since I installed it | Red is on constant power (common in cars with no ACC position), or blue/white feeds an amp's power terminal | Key off: red must read 0 V. Move red to an ignition-detecting terminal. Make sure blue/white goes only to the remote or relay control terminal. |
| The display shows AMP ERROR and there is no sound | A speaker lead is shorted, a negative lead is grounded, negatives are joined together, or the load is below 4 Ω | Key off: inspect each speaker pair for bare strands touching metal. Separate any joined negatives. Measure each speaker; it must not be 1 to 3 Ω. Then turn the ignition off and back on. |
| The sound is thin with no bass, and it seems to come from nowhere | One speaker is wired with reversed polarity | Check that white, gray, green and violet go to the + terminals and the black-striped leads go to −. Correct any reversed pair. |
| My external amplifier never turns on | Blue/white is not connected, or it goes to the wrong terminal | With the unit on, measure about 12 V on blue/white at the amp's system remote terminal. Also check the amp's own power, fuse and separate ground. |
| The amp turns on but there is no sound from the subwoofer on SUB OUT | The subwoofer output is disabled or the output mode is wrong | Set SUBWOOFER to ON. In SP-P/O MODE, choose REAR/SUB.W or SUB.W/SUB.W, not REAR/REAR. Then check that the RCA cable is plugged into SUB OUT. |
| My 2 Ω subwoofer on the rear leads is weak, distorted or cuts out | It is wired to green instead of violet, or REAR-SP is still set to FUL | Move the subwoofer to violet and violet/black, tape green and green/black, and set REAR-SP to SW. Confirm the subwoofer is rated over 70 W. |
| The power antenna does not go up, or radio reception is very poor | Blue/white is not on the antenna relay control or booster terminal, or the ANT plug is loose | With the unit on, check for 12 V at the relay control or booster supply terminal. Reseat the antenna plug fully in ANT. |
| The display does not dim when I turn on the headlights | Orange/white is not connected, or the dimmer setting is wrong | With the lights on, measure 12 V on orange/white. Set DIM SETTING to SYNC ILLUMI. |
| The radio acts strangely or shows odd messages right after installation | The microprocessor was not reset after installation | Remove the front panel, press RESET with a pointed tool longer than 8 mm, then turn the ignition on again. |






