Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
VTM-4 Control Unit Inputs and Outputs
2002 Honda Civic SiSECTION VTM-4 Control Unit Inputs and Outputs
WARNING: This page is about a different car, the 2006 Acura MDX, 2005 Acura MDX, 2004 Acura MDX, and 2003 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
The VTM-4 control unit terminal voltage and measuring conditions for the 4WD control system are shown.
TERMINAL CONDITION SPECIFICATION
| Terminal number | Wire color | Terminal sign (Terminal name) | Description | Measurement | |
|---|---|---|---|---|---|
| Conditions | Voltage | ||||
| A1 | YEL | IG1 (Ignition 1) | Power supply for activating the system | Ignition switch ON (II) | Battery Voltage |
| A3 | GRY/RED | RRP (Rear right pulse) | Detect right-rear wheel sensor signal | Turn wheel at 1 rotation/second | 2-3 V Turn real slow 5V Faster pulse 0-5 V |
| A4 | ORN/GRN | FSR (Fail-safe relay) | Drives VTM-4 relay | Ignition switch ON (II) | Battery Voltage |
| Engine running | Below 1 V | ||||
| A5 | GRY/YEL | RLP (Rear left pulse) | Detects left-rear wheel sensor signal | Turn wheel at 1 rotation/second | 2-3 V Turn real slow 5V Faster pulse 0-5 V |
| A6 | GRN/RED | PARBRK (Parking brake) | Detects parking brake signal | Parking brake on | Below 2 V |
| Parking brake off | Battery Voltage | ||||
| A7 | LT GRN | FRP (Front right pulse) | Detects right-front wheel sensor signal | Turn wheel at 1 rotation/second | 2-3 V Turn real slow 5V Faster pulse 0-5 V |
| A8 | BRN/WHT | LOCKSW (Lock button) | Detects VTM-4 LOCK button signal | Ignition switch ON (II) | Below 1 V |
| VTM-4 lock mode | Battery Voltage | ||||
| A9 | WHT/RED | FLP (Front left pulse) | Detects left-front wheel sensor signal | Turn wheel at 1 rotation/second | 2-3 V Turn real slow 5V Faster pulse 0-5 V |
The VTM-4 control unit terminal voltage and measuring conditions for the 4WD control system are shown.
TERMINAL CONDITION SPECIFICATION
| Terminal number | Wire color | Terminal sign (Terminal name) | Description | Measurement | |
|---|---|---|---|---|---|
| Conditions | Voltage | ||||
| A10 | BLK | LG1 (Logic ground) | Ground | Below 1 V | |
| A11 | WHT | CANH (CAN communication signal high) | CAN communication signal | Ignition switch ON (II) | 2.0-4.5 V |
| A12 | GRN/BLU | NEP (Engine revolution) | Detects engine revolution signal | Ignition switch ON (II) | Above 8 V |
| Engine running at 1,000 rpm | 5-8 V | ||||
| A13 | BLK | TCL (Temperature coil low) | Detects differential oil temperature sensor signal | Check at normal temperature with the ignition switch ON (II) | 1-3.6 V |
| A14 | RED/WHT | WARN 1 (Warning 1) | Drives VTM-4 indicator | VTM-4 indicator on | Below 4 V |
| VTM-4 indicator off | Battery Voltage | ||||
| A15 | WHT | TCH (Temperature coil high) | Power supply for differential oil temperature sensor | Check at normal temperature with the ignition switch ON (II) | 4-5 V |
| A16 | YEL/BLK | LOCKL (Lock lamp) | Drives VTM-4 LOCK indicator | VTM-4 LOCK indicator on | Below 4 V |
| VTM-4 LOCK indicator off | Battery Voltage | ||||
| A18 | LT BLU | LET (Line end tester) | Communication signal to HDS | Ignition switch ON (II) (Not connected to HDS) | About 5 V |
| A20 | BRN | SCS (Service check signal) | Detects service check connector signal | SCS circuit shorted | Below 2 V |
| SCS circuit opened | About 5 V | ||||
| A22 | RED | CANL (CAN communication signal low) | CAN communication signal | Ignition switch ON (II) | 0.5-3.0 V |
| B1 | BLK/RED | LCOH (Left coil high) | Drives left clutch electromagnetic coil (positive) | Ignition switch ON (II) | Below 1 V |
| Engine running | Below 1 V | ||||
| VTM-4 lock mode | Above 3 V | ||||
| B2 | BLK/WHT | LCOL (Left coil low) | Drives left clutch electromagnetic coil (negative) | Ignition switch ON (II) | Below 1 V |
| Engine running | Below 1 V | ||||
| VTM-4 lock mode | Below 1 V | ||||
| B3 | BRN | RCOH (Right coil high) | Drives right clutch electromagnetic coil (positive) | Ignition switch ON (II) | Below 1 V |
| Engine running | Below 1 V | ||||
| VTM-4 lock mode | Above 3 V | ||||
| B4 | GRN | RCOL (Right coil low) | Drives right clutch electromagnetic coil (negative) | Ignition switch ON (II) | Below 1 V |
| Engine running | Below 1 V | ||||
| VTM-4 lock mode | Below 1 V | ||||
| B5 | BLK | PG (Power ground) | Ground | Below 0.5 V | |
| B7 | RED/BLU | PWR (Power) | Power supply for VTM-4 control unit | 10 seconds after ignition switch ON (II) | Below 3 V |
| Engine running | Battery Voltage | ||||
| VTM-4 lock mode | Above 8 V | ||||
| B11 | RED/WHT | WARN 2 (Warning 2) | Drives VTM-4 indicator | VTM-4 indicator on | Below 4 V |
| VTM-4 indicator off | Battery Voltage | ||||
| B12 | BLK | LG2 (Logic ground) | Ground | Below 1 V | |
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.