Mercedes EQA / EQB vs MG eléctrico (MG4, ZS EV, Marvel R): which engine is more reliable?

According to our risk index, the MG eléctrico (MG4, ZS EV, Marvel R) carries less risk than the Mercedes EQA / EQB: 20/100 (low risk) versus 36/100 (moderate risk). The Mercedes EQA / EQB has 2 documented serious faults, the main one being «Internal short circuit in the high-voltage battery: fire risk, software update and battery replacement»; the MG eléctrico (MG4, ZS EV, Marvel R) has 1 documented serious fault, the main one being «High-voltage system fault warning and loss of propulsion».

Risk index

Mercedes EQA / EQB

Moderate risk · 2 serious faults

Risk index

MG eléctrico (MG4, ZS EV, Marvel R)

Low risk · 1 serious fault

Lower risk

The index (0–100) weights the severity and frequency of the three most serious documented faults. How it is calculated

Reviewed on 30 October 202616 sources How we work

Is the Mercedes EQA / EQB reliable?

The only well-documented faults in the EQA and EQB electric drivetrain are the battery recalls for fire risk (2025 and 2026, the latter with battery replacement) and a 2024 pyrofuse check. No recurring faults have been published.^[1][2][3][4]

See the 2 of the Mercedes EQA / EQB faults

Is the MG eléctrico (MG4, ZS EV, Marvel R) reliable?

MG electric cars have few documented battery or motor faults; the most cited is AC charging, which is sometimes rejected or interrupted. What Car? places the MG4 in the lower part of its survey, mainly for minor electronics.^[5][6][7]

See the 2 of the MG eléctrico (MG4, ZS EV, Marvel R) faults

Side-by-side comparison

Comparison of Mercedes EQA / EQB and MG eléctrico (MG4, ZS EV, Marvel R)
Item	Mercedes EQA / EQB	MG eléctrico (MG4, ZS EV, Marvel R)
Technical data
Type	Engine	Engine
Fuel	Electrical	Electrical
Displacement	—	—
Timing	—	—
Power	190–292 hp	143–435 hp
Production	since 2021^[8]	since 2019^{[9][10][11][12]}
Reliability
Risk index (what is it?)	36Moderate risk	20Low risk
Documented faults	2	2
Of high or critical severity	2	1
Worst severity	Critical severity	High severity
Main faults	Critical severity: Internal short circuit in the high-voltage battery: fire risk, software update and battery replacement Critical severity: Displaced pyrofuse housing: possible pyrotechnic fuse failure and loss of power	Medium severity: Charging faults: on-board charger and interrupted charging High severity: High-voltage system fault warning and loss of propulsion
Most expensive documented repair	No reliable data	No reliable data
Which versions to buy
BuyRecommended versions	None	ZS EV Long Range 72.6 kWh, 177 hp (2021-2024)^[13]
With cautionVersions to be cautious about	EQA 250, 300 4MATIC and 350 4MATIC, 69.7 kWh (2021-present)^[1][2][3] EQA 250+, 73.9 kWh, 190 hp (2022-present)^[3][14]	MG4 Standard Range 51 kWh LFP, 170 hp (2022-present)^[6] MG4 Long Range 64 kWh, 204 hp (2022-present)^[5] MG4 Extended Range 77 kWh, 245 hp (2023-present)^[5][6] MG4 XPower 64 kWh, 435 hp (2023-present)^[15] ZS EV 44.5 kWh, 143 hp (2019-2021)^[16] ZS EV Standard Range 51 kWh LFP, 150 hp (2022-2024)^[13] Marvel R Comfort/Luxury 70 kWh, 180 hp (2021-2024)^[7] Marvel R Performance 70 kWh, 288 hp (2021-2024)^[7]
AvoidVersions to avoid	None	None

Severity of each fault: green, low; amber, medium; red, high; dark red, critical. How we rate them

Cars that each one is fitted to

Mercedes EQA / EQB

MG eléctrico (MG4, ZS EV, Marvel R)

Other comparisons

With the Mercedes EQA / EQB

With the MG eléctrico (MG4, ZS EV, Marvel R)

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Sources

Every fact on this page links to its source. If you find an error, let us know.

Recall: Mercedes-Benz EQA (2021 - 2024) EV/Hybrid, fire (2025)car-recalls.eu · Other source · published 5 April 2025 · consulted 30 October 2026
Recall: Mercedes-Benz EQA (2021 - 2024) EV/Hybrid, fire (2026)car-recalls.eu · Other source · published 8 March 2026 · consulted 30 October 2026
Segunda llamada a revisión de los Mercedes EQA y EQB por riesgo de incendio. Toca cambiar la bateríaAutofácil · Motoring press · published 15 April 2026 · consulted 30 October 2026 · in Spanish
Recall: Mercedes-Benz EQA (2024) electronic, injury (pirofusible)car-recalls.eu · Other source · published 25 October 2024 · consulted 30 October 2026
Fiabilité Mg MG4 (2023): toutes les pannes connuesFiches-auto.fr · Reliability study · consulted 30 October 2026 · in French
Used MG4 2022-present reliabilityWhat Car? · Reliability study · consulted 30 October 2026
Fiabilité Mg Marvel R (2021): toutes les pannes connuesFiches-auto.fr · Reliability study · consulted 30 October 2026 · in French
Mercedes-Benz EQAWikipedia · Other source · consulted 30 October 2026
MG4 EVWikipedia · Other source · consulted 30 October 2026
MG ZS (crossover): sección MG EZS / ZS EVWikipedia · Other source · consulted 30 October 2026
Datos generales MG MG4 Electric Luxury (05/23 - 07/25)ADAC · Technical documentation · consulted 30 October 2026 · in German
MG Marvel R Electric: motores, equipamiento y preciosCarnovo · Technical documentation · published 21 July 2023 · consulted 30 October 2026 · in Spanish
Fiabilité Mg ZS: toutes les pannes connuesFiches-auto.fr · Reliability study · consulted 30 October 2026 · in French
Es probable que Mercedes sustituya las baterías de los modelos EQA y EQB en Alemaniaelectrive · Motoring press · published 17 February 2026 · consulted 30 October 2026 · in Spanish
Foro GoingElectric: MG4 XPower con fallo del sistema de control y sin cargaGoingElectric · Owners' forum · consulted 30 October 2026 · in German
Foro MGEVs: batería de tracción de un ZS EV de 2019 averiada con menos de 22.000 millasMGEVs.com · Owners' forum · published 26 August 2025 · consulted 30 October 2026