# OBD Scanner
> **Field diagnostics. 80% repair cap. One-time use per system.**
## Overview
The **OBD Scanner** is a hand-held diagnostic tool that lets you identify and repair [[Malfunctions|vehicle malfunctions]] in the field without returning to the shop.
**Purchase**: Available in Shop → Tools (\$1,500-3,000 depending on game difficulty)
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## How It Works
### Basic Operation
1. **Equip** OBD Scanner (purchase from shop)
2. **Approach Vehicle** - Walk up to any owned vehicle
3. **Activate** - Press action key (default: O)
4. **Scan** - Tool displays vehicle health and active malfunctions
5. **Diagnose** - Select suspected cause from symptoms
6. **Repair** - Apply field fix (consumes scanner)
The OBD Scanner hand tool - portable field diagnostics
Select which system to diagnose: engine, hydraulics, electrical, tires, or paint
### The 80% Cap
OBD Scanner repairs **restore reliability to maximum 80%**:
| Before Repair | After OBD Repair | Full Shop Repair |
|---------------|------------------|------------------|
| 45% reliability | 72% (80% of 90% max) | 100% |
| 60% reliability | 80% (capped) | 100% |
| 35% reliability | 56% (80% of 70% max) | 100% |
**Why the cap?**: Field repairs are temporary fixes. For full restoration, use [[Service-Truck]].
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## Diagnosis System
### Reading Symptoms
OBD Scanner presents **symptoms** (what you observe):
- "Engine misfiring at high RPM"
- "Hydraulic pressure fluctuating"
- "Alternator voltage low"
You must **select the root cause**:
- ✅ Correct diagnosis → 80% repair
- ⚠️ Close diagnosis → 60% repair
- ❌ Wrong diagnosis → 30% repair (waste scanner)
Engine system scan showing reliability, temperature, and Real Vehicle Breakdowns integration
Comprehensive health report with actionable recommendations
### Difficulty Levels
| Game Difficulty | Symptom Clarity | Hints | Diagnosis Attempts |
|-----------------|----------------|-------|-------------------|
| Easy | Obvious symptoms | Clear hints | 2 attempts before failure |
| Normal | Moderate clues | Vague hints | 1 attempt |
| Hard | Cryptic messages | No hints | 1 attempt, no confirmation |
**Tip**: In Hard mode, study [[Malfunctions]] page before using scanner. Wrong guess = wasted \$2,000.
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## Integration Features
### [[RVB-Integration|RVB Display]]
If Real Vehicle Breakdowns is installed:
- OBD Scanner shows **both UsedPlus AND RVB faults**
- Separate tabs for each system
- Can diagnose UsedPlus malfunctions only
- RVB repairs require RVB's repair system
### [[UYT-Integration|UYT Tire Service]]
With Use Up Your Tyres installed:
- OBD Scanner detects flat tires
- Shows tire wear % for all 4 tires
- Can apply **emergency tire repair**:
- **Patch**: Restores to 30% condition (\$100)
- **Plug**: Restores to 50% condition (\$200)
- Not a replacement, just enough to get home
### Fluid Refills
OBD Scanner can **top off fluids** in the field:
- Engine oil
- Hydraulic fluid
- Coolant
**Limitation**: Can't change oil (clears contaminants), only add more. Full service requires shop.
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## Strategic Use
### When to Use OBD Scanner
✅ **Good situations**:
1. In middle of harvest, can't afford downtime
2. Vehicle at 65% reliability, needs quick boost
3. Remote field, shop is 2km away
4. Minor issue, not worth \$5k shop bill
❌ **Don't waste on**:
1. Vehicle below 50% reliability (needs Service Truck)
2. Major failures (transmission, engine rebuild)
3. When at shop anyway (just use shop repair)
4. Unknown problem (study symptoms first)
### Cost-Benefit
**Example: Hydraulic Leak**
- Shop repair: \$1,200 + 30 min downtime
- OBD Scanner: \$2,000, instant, 80% fix
- **You pay \$800 more** for convenience
If vehicle is at 55% reliability and leak repair brings it to 80%, you get:
- 25 percentage points of reliability
- \$2,000 / 25 = **\$80 per reliability point**
Compare to Service Truck (can restore from 50% → 100% at \$50/point). OBD Scanner is emergency tool, not economical long-term solution.
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## One-Time Use Per System
**Critical limitation**: OBD Scanner can repair each vehicle **system** (engine, hydraulic, electrical) **only once**.
After first use on a system:
- Scanner displays: "This system requires workshop equipment for further service"
- Must use shop repair or [[Service-Truck]] for additional fixes
**Example**:
1. Day 1: Use OBD on engine misfire → Works, 80% repair
2. Day 30: Engine develops oil leak → OBD Scanner refuses
3. Solution: Shop repair or Service Truck
### Why One-Time?
Prevents players from using \$2k scanner to avoid \$20k Service Truck investment. OBD is **emergency tool**, not permanent solution.
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## Tips & Strategies
### ✅ Smart Scanner Use
1. **Study First** - Read malfunction symptoms before scanning
2. **Save for Harvest** - Don't use preemptively, wait for actual failure
3. **Combine with Maintenance** - Use scanner, then schedule full service later
4. **Triage Tool** - Diagnose in field, decide if worth shop trip
### ❌ Common Mistakes
1. **Guessing Diagnosis** - Wrong guess = wasted \$2,000
2. **Using Too Early** - At 85% reliability, just finish the day
3. **Expecting Permanent Fix** - 80% cap means problems return eventually
4. **Not Planning** - Use scanner then forget about underlying issue
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## Troubleshooting
**"Scanner won't activate"**
- Must be on foot (not in vehicle)
- Vehicle must be owned by you
- Vehicle must have active malfunction
**"Diagnosis failed"**
- Wrong root cause selected
- In Hard mode, no second chance
- Scanner consumed anyway
**"System requires workshop"**
- Already used OBD on this system once
- Use shop repair or Service Truck instead
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## Related Pages
- [[Malfunctions]] - What breaks and why
- [[Service-Truck]] - Permanent reliability restoration
- [[RVB-Integration]] - OBD + RVB integration
- [[UYT-Integration]] - Tire service features
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**Next**: Learn about the [[Service-Truck]] for restoring reliability above 80%.