Engine & fuel system
4 documented faults — symptoms, causes and workshop fixes.
Engine difficult to start
Spark plugs contaminated with carbon deposits.
Overview
- Affects
- All models with 1KR-FE engine code.
- Fault codes
P0420P0300P0303
Symptoms
Engine malfunction indicator lamp (MIL) illuminated. Engine misfire. Trouble codes stored: P0420, P0300, P0303.
Repair steps
- Replace spark plugs.
- Check operation and condition of catalytic converter. Replace if necessary.
- Check operation and condition of heated oxygen sensor (HO2S). Replace if necessary.
- Check for diagnostic trouble codes and delete as necessary.
Data: Motorwise Workshop. Bulletin 1.
Failure to start
Ignition switch faulty. Fix: fit a modified part.
Overview
- Affects
- All models, →09/08.
- Remedy
- Fit modified part
Symptoms
Ignition switch sticks in start position. Possible damage to engine wiring harness. Starter motor burns out. Starter motor not disengaging.
Repair steps
- Fit modified ignition switch.
- Check engine wiring harness for damage. Replace as necessary.
- Check starter motor for damage. Replace as necessary.
Parts
| Part | Part number | Qty |
|---|---|---|
| Ignition switch repair kit | 69057-0H011-84 | 1 |
| Engine wiring harness (1KR-FE) | Refer to manufacturer | 1 |
| Starter motor | Refer to manufacturer | 1 |
Data: Motorwise Workshop. Bulletin 9.
Rattling noise from exhaust tail pipe when accelerating
Overview
- Affects
- All models, →08/09.
- Remedy
- Fit modified part
- Parts
- 2 parts
Cause
Unsatisfactory design of rear exhaust silencer.
Repair
- Fit modified rear silencer.
- Fit modified rear exhaust silencer mounting rubbers.
Parts2 parts
| Part | Part number | Qty |
|---|---|---|
| Rear silencer | 17430-0Q013 | 1 |
| Exhaust silencer mounting rubber | 17588-0Q010 | 2 |
Data: Motorwise Workshop. Bulletin 11.
Engine malfunction indicator lamp (MIL) illuminated. Trouble code stored: P0420
Symptoms
Lack of power.
Cause
Catalytic converter breaks up internally and blocks exhaust system.
Repair
- Check operation and condition of catalytic converter. Replace if necessary.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Catalytic converter | 17140-0Q020, or 17140-0Q010 | 1 |
Data: Motorwise Workshop. Bulletin 14.
Electrical & ignition
1 documented fault — symptoms, causes and workshop fixes.
Airbag warning lamp flashes continuously
Overview
- Affects
- All models.
- Fault codes
B1000- Remedy
- Fit modified part
Symptoms
Trouble code stored: B1000.
Cause
SRS control module faulty.
Repair
- Carry out electrical, mechanical and component tests (as applicable) to eliminate any other possible cause(s).
- If no fault(s) found: Fit modified SRS control module.
Data: Motorwise Workshop. Bulletin 6.
Clutch & gearbox
3 documented faults — symptoms, causes and workshop fixes.
Clutch slip
Overview
- Affects
- All models with manual transmission, →10/08.
- Remedy
- Fit modified part
- Parts
- 2 parts
Symptoms
Squealing noise from clutch on engagement. Strong odour from clutch.
Cause
Clutch centre plate vibrating on transmission input shaft.
Incorrect clutch pedal free play.
Poor manufacture of clutch assembly.
Repair
- Check clutch pedal adjustment, ensure adequate free play.
- Fit modified clutch assembly.
Parts2 parts
| Part | Part number | Qty |
|---|---|---|
| Clutch centre plate | 31250-0H040 | 1 |
| Clutch pressure plate | 31210-0H040 | 1 |
Data: Motorwise Workshop. Bulletin 5.
Poor gear shifting
Overview
- Affects
- All models with 5-speed MT, →06/13.
- Remedy
- Fit modified part
Symptoms
Clutch slip. Squealing noise from clutch on engagement. Strong odour from clutch.
Cause
Broken clutch release bearing.
Worn clutch centre plate due to excessive clutch slip.
Incorrect clutch pedal free play.
Clutch release lever faulty.
Repair steps
- Fit modified clutch assembly.
- Inspect clutch release lever for damage and replace if necessary.
- Check clutch pedal adjustment, ensure adequate free play.
Data: Motorwise Workshop. Bulletin 12.
Poor starting
Overview
- Affects
- All models with auto shift manual (ASM) transmission, →06/13.
- Remedy
- Fit new part
- Parts
- 3 parts
Symptoms
Poor gear shifting. Unable to select 1st gear.
Cause
Broken clutch release bearing.
Excessive wear on clutch pressure plate diaphragm spring due to faulty clutch release lever.
Repair
- Fit new clutch assembly.
- Fit new clutch release lever.
Parts3 parts
| Part | Part number | Qty |
|---|---|---|
| Clutch centre plate | 31233-0H010 | 1 |
| Clutch assembly | 31210-79015 | 1 |
| Clutch release bearing | 31230-0H011 | 1 |
Data: Motorwise Workshop. Bulletin 13.
Body & trim
6 documented faults — symptoms, causes and workshop fixes.
Rattling noise from front seat belt lower anchorage point area over uneven surfaces
Cause
Excessive movement between front seat belt lower anchorage point bolt and seat belt.
Repair
- Fit spacer sleeve to front seat belt lower anchorage point bolt.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Spacer sleeve | 73132-0H010 | 1 |
Data: Motorwise Workshop. Bulletin 2.
Water ingress into rear of passenger compartment
Cause
Rear door glass deformed.
Repair
- Renew weather seal at front of rear door glass.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Weather seal | 67873-0H011 | 1 |
Data: Motorwise Workshop. Bulletin 3.
Rattling noise from front passenger's seat when unoccupied
Cause
Front passenger's seat runner assembly vibrating.
Repair
- Fit modified seat runner assembly.
Data: Motorwise Workshop. Bulletin 4.
Water ingress into passenger compartment through front or rear door weather seals
Cause
Incorrectly manufactured door weather seals.
Repair
- Fit modified door weather seals as necessary.
Parts2 parts
| Part | Part number | Qty |
|---|---|---|
| Weather seal | 62381-70010 | 2 |
| Weather seal | 62381-70020 | 2 |
Data: Motorwise Workshop. Bulletin 8.
Water ingress into load area
Symptoms
Rear footwell carpet wet.
Cause
Damaged or incorrectly fitted air ventilation outlet grilles, located behind rear bumper.
Repair
- Check fitment and condition of air ventilation outlet grilles, replace if necessary.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Air ventilation outlet grille | 62930-0H010 | 2 |
Data: Motorwise Workshop. Bulletin 10.
Difficult to insert and turn key in door lock barrel
Overview
- Affects
- All models without remote controlled central locking, →06/13.
- Remedy
- Fit modified part
- Parts
- 1 part
Cause
Unsatisfactory design of door lock barrel.
Repair
- Fit modified door lock barrels.
- Program all new keys to immobilizer control module.
Parts1 part
| Part | Part number | Qty |
|---|---|---|
| Door lock barrel set | 69005-0H911 | 1 |
Data: Motorwise Workshop. Bulletin 15.
Other
1 documented fault — symptoms, causes and workshop fixes.
Unable to select gears
Cause
Gear selector cable connection broken.
Repair
- Fit modified gear selector cable.
Parts2 parts
| Part | Part number | Qty |
|---|---|---|
| Gear selector cable - 1,0 | 33820-0H010 | 1 |
| Gear selector cable - 1,4 D-4D | 33820-0H020 | 1 |
Data: Motorwise Workshop. Bulletin 7.
Glossary
Technical terms used in this guide.
- MIL
- Malfunction indicator lamp — the engine warning light on the dashboard
- VIN
- Vehicle identification number — 17 characters, found at the base of the windscreen and on the V5C logbook
- Trouble Codes
- Standardised fault codes stored by the engine control module, read with a diagnostic tool
- SRS
- Supplementary restraint system — the airbags and seat-belt pretensioners
- Control Module
- A control unit for one of the vehicle's systems (engine, gearbox, brakes, body, and so on)
- Immobilizer
- The anti-theft system that prevents the engine from starting without the correct key
- Selector Cable
- The cable that connects the gear lever to the gearbox
- Trouble Code
- A standardised fault code stored by a control module, read with a diagnostic tool
- Wiring Harness
- The bundled cables that carry power and signals around the vehicle
- Misfire
- One or more cylinders not firing correctly — the engine runs roughly or loses power
Frequently asked questions
What are the common faults with the Toyota Aygo 1.0?
This guide contains 15 workshop bulletins for the Toyota Aygo 1.0. Of these, six concern the body and trim and four the engine and fuel system. Symptoms, causes, repair steps and part numbers are shown where supplied.
Does every Toyota Aygo 1.0 have these faults?
No. These are patterns documented across the model by workshops, not predictions for an individual vehicle. Where a fault applies only to certain vehicles or VIN ranges, that is listed with the fault.
Can I check for Toyota Aygo 1.0 faults myself?
Many of them. The documented symptoms can be seen, heard or felt during a test drive.