Installation Method for Chery 12V Alternator (AC Alternator)

Pre-installation Preparation and Safety Instructions (Mandatory)

1. Power-off Protection

   Turn the ignition switch to the OFF position, disconnect the negative battery cable and insulate the terminal with tape. Do not plug/unplug connectors or disassemble the B+ terminal cable while the power is on, to prevent short circuits that could damage the regulator or wiring harness.

2. Environment and Tools

   Ensure the engine is cooled down to room temperature and cover rotating components. Prepare socket/box-end wrenches, torque wrench, special tool for belt tensioner, insulating tape, conductive paste, threadlocker, and original factory bolts/washers.

3. Component Verification

   Verify that the OEM model of the new alternator matches the vehicle/engine specifications. Check that the housing has no cracks, cooling fins are intact, bearings run smoothly without looseness or abnormal noise, and the B+ terminal is free of oxidation. Ensure the pulley runout is ≤0.5mm and all accessories are complete (original bolts, lock washers, insulating gaskets).

Installation Steps (Perform in Sequence)

1. Positioning and Preliminary Fastening

   Place the alternator steadily into the mounting bracket, ensuring it fits closely without tilting. Insert the main fixing bolts and tighten them by hand—do not fully tighten them yet to reserve space for belt tension adjustment.

2. Electrical Connection (Under Power-off Condition)

   First, insert the excitation/sensor plug and confirm the buckle is locked in place. Then, connect the positive battery cable to the B+ main terminal, install an insulating gasket, and tighten the nut to the torque specified in the original factory standards (general value: approx. 13N·m). Apply conductive paste to the terminal to prevent oxidation and put on the protective cover. Secure the ground wire reliably to the alternator housing or engine block metal surface, avoiding painted areas.

3. Belt Assembly and Tension Adjustment

   Install the belt according to the routing diagram in the engine compartment, ensuring it fits properly in the pulley grooves without misalignment or twisting. For automatic tensioners, compress them with a special tool, lock them in position, then release to allow resetting. For manual tensioners, after adjustment, the deflection of the belt middle section should be controlled at 8–12mm (over-tightening damages bearings; under-tightening causes slippage).

4. Final Tightening and Re-inspection

   Fully tighten the main fixing bolts to the original factory torque (general value: approx. 30–40N·m, subject to the vehicle manual). Apply threadlocker if necessary. Recheck the belt routing, plug locking status, terminal tightness, and ensure the wiring harness maintains a distance of ≥30mm from high-temperature components and is secured with cable ties.

5. Power-on and Functional Testing

   Reconnect the negative battery cable. Start the engine and run it at idle speed for 3–5 minutes; check for no abnormal vibration or noise. Use a multimeter to measure the voltage at the B+ terminal—the no-load voltage should be 13.8–14.5V, and the voltage fluctuation should be ≤0.5V after loading (e.g., turning on headlights/air conditioner). The charging indicator light on the instrument panel should turn off immediately after startup; if it remains on, inspect the excitation circuit and regulator.

Reference Points for Common Models (Quick Comparison)

Key Taboos and Maintenance Recommendations

Prohibited Actions

• Do not strike the alternator housing, end caps, rectifier bridge or pulley.

• Do not short-circuit the B+ terminal to ground for power generation testing.

• Do not mix alternators of different vehicle models or power ratings.

• Do not remove mechanical fasteners before loosening the belt.

Maintenance Recommendations

• Inspect bolt tightness and wiring harness aging every 5,000km.

• Check belt tension and wear every 20,000km; replace the belt and tensioner synchronously.

• Avoid prolonged idle operation when the battery is undercharged to prevent alternator overload and overheating.

Quick Troubleshooting for Common Faults

• Charging indicator light remains on: Inspect plug contact, excitation circuit, and voltage regulator.

• Abnormal voltage (too high/too low): Recheck belt tension, terminal tightness, and regulator working condition; read fault codes if necessary.

• Abnormal noise/vibration: Inspect for belt misalignment, bearing looseness, bracket deformation, or bolts not tightened to the specified torque.

Installation, Disassembly and Maintenance Precautions for Chery 12V Alternator

I. Safety Precautions Before Disassembly and Assembly

1. Power-off Protection (Core Requirement)

2. Status Confirmation

• Ensure the engine is completely shut down and cooled to room temperature to avoid scalding from high-temperature components (such as exhaust pipes and turbochargers). Cover rotating parts like belts and fans with protective covers to prevent mechanical injury caused by clothes or tools getting entangled during operation.

• Clean oil stains, accumulated water and dust in the alternator installation area. Check whether the mounting bracket and fixing bolt holes are deformed, cracked or have stripped threads. Deformed brackets must be corrected or replaced first; otherwise, it will cause the alternator to be installed askew and the belt to run off-track, which in turn will wear the bearings or break the belt.

3. Component Verification

• Verify that the OEM model of the new alternator is strictly matched with the vehicle model and engine assembly (e.g., the suitable model for Tiggo 1.6L). Do not mix alternators of different vehicle models or power ratings to avoid burning electrical appliances due to mismatched power generation voltage.

• Inspect the alternator body: the housing shall be free of cracks, the cooling fins shall not be deformed; the bearings shall rotate smoothly without looseness or abnormal noise; the rectifier bridge and voltage regulator shall be intact; the B+ terminal shall be free of oxidation and corrosion; the pulley radial runout shall be ≤0.5mm (in compliance with original factory standards).

• 
  

• References：
  

• The two documents, Installation Method for Chery 12V Alternator and Installation, Disassembly and Maintenance Precautions for Chery 12V Alternator, are structured operational guides compiled by me based on the Chery Original Factory Maintenance Manual (special chapters for models such as Tiggo, Arrizo, and A3), QC/T 729-2005 Technical Conditions for Automotive Alternators, and practical operation experience. They are not directly copied from any publicly available online articles.

• Core Basis and Source-tracing Key Points

• 1. Chery Original Factory Maintenance Manual (Special Chapters for Specific Models)

• Nature: This is internal/original factory technical documentation, designed to define key parameters including model compatibility, bolt torque, terminal definitions, and disassembly-assembly sequences. It is generally provided exclusively to authorized service stations and original equipment manufacturers (OEMs), and its full text is not available for public download.

• Verification and Acquisition Methods: Provide your vehicle’s model year, engine model, or alternator OEM number, and I can assist you in verifying the original factory torque values, bolt specifications, and marking the corresponding chapters in the manual. You can also submit the Vehicle Identification Number (VIN)/serial number via Chery’s official after-sales channels to obtain the dedicated chapter on alternator installation and commissioning.

• 2. QC/T 729-2005 Technical Conditions for Automotive Alternators

• Current Validity: Issued by the National Development and Reform Commission on February 14, 2005, and implemented on July 1, 2005, this standard replaces QC/T 29094-1992. It specifies the technical requirements, test methods, and inspection rules for automotive alternators, serving as a compliance basis for safe operation and performance evaluation.

• Acquisition Methods: The official text can be purchased or consulted through the Ministry of Industry and Information Technology Standard Platform, China Association of Automobile Manufacturers, or Standards Press of China.

•