Network info for Yes (Malaysia)

Some tidbits:

Operates own 4G LTE-only network in Malaysia.
5G is available through Digital Nasional Berhad’s network.
Operated/brand by YTL Communications Sdn Bhd (YTLC).
PLMN @ MCC/MNC code: 502 152
Was a provider for Malaysia’s 1BestariNet program
Operated its own WiMAX network until October 2019.
Doesn’t have 4G/3G/2G domestic roaming agreement with other telcos.

5G NR frequency bands:

You need a 5G-capable plan & SIM (Yes FT5G/Infinite) to access 5G. You can’t access 5G on your 5G SIM if you’ve been downgraded to 4G profile. However, some of the 4G SIMs (Prihatin/Kasi Up/etc.) may be provisioned with 5G access (either LTE B28 only or both LTE B28 + 5G n78)

5G through Yes on iPhones is enabled in iOS 16.4 which comes with generic profile that supports 5G by default. You need to upgrade to iOS 17.1 for official Apple support.

4G LTE frequency bands:

LTE Band number	Frequency	Duplex mode	Bandwidth
20	800MHz	FDD	2x5MHz
38/41	2600MHz/2500MHz	TDD	20MHz
40	2300MHz	TDD	20MHz (all of WM, parts of EM), 10MHz (parts of EM)

Band 38 & Band 41 is a MFBI of YTLC’s 2600MHz spectrum, not all Yes cell towers has MFBI support. Asiaspace’s 30MHz worth of 2300MHz spectrum sharing with YTLC is only in West Malaysia.

Note that Yes configured their 2300MHz B40 spectrum as follows:

West Malaysia: 60MHz (YTLC + Asiaspace) split into three 20MHz channels with different freq range
East Malaysia: Some of the towers in East Malaysia uses same frequency range (EARFCN 39150) for all B40 sectors. Some of them (mostly in Sabah(?)) splits 30MHz of B40 to 3 individual 10MHz sectors with different freq range.

If you’re using 5G-capable phone/modem and lock it to prefer LTE in phone settings, LTE B28 is put into lowest priority which means the phone/modem will always prefer LTE B20/B38/B40/B41 unless in areas where Yes own 4G signal is weak and DNB’s LTE B28 signal is strong.

VoLTE (Voice over LTE) support:

Yes, supported (required for making/receiving calls and sending/receiving SMS)
VoLTE support is already included by default.
VoLTE/IMS services support for Apple iPhones needs iOS 17.1 onwards for better realibility as Apple included Yes’ own carrier bundle with iOS 17.1. Prior to iOS 17.1, calls/SMS support may be wonky.
Yes doesn’t seem to do device whitelisting, so theoretically any VoLTE-capable device should work with Yes’ VoLTE.
Yes uses AMR-WB for calls.
VoLTE works on across all Yes LTE bands.

VoWiFi (Voice over WiFi) support:

Supported, in testing phase for certain Yes numbers.
You need latest software update on your phone for increased chance to have VoWiFi.
Xiaomi users on MIUI can try dialing *#*#869434#*#* to disable VoWiFi carrier check.
iPhones are supported too.
VoWiFi works while roaming.

eSIM support:

Supported, you can check devices that supports Yes eSIM here.

Apple iPhones should work too.

Carrier billing support:

Not supported yet on Google Play.
Apple’s App Store isn’t supported too.

APN settings:

Name: (anything)
APN: yesnow (4G SIM), yesnet5 (5G SIM)
APN type: default,ims
APN protocol: IPv4/IPv6

Yes accepts anything written in the APN field and it’ll redirect to yesnow (4G SIM) or yesnet5 (5G SIM).

More info:

Call forwarding is supported. (make sure the line stays active)
Legacy unlimited individual postpaid plans (KU49, KU79, KU99) are not transferable to another person
Yes does not use any USSD codes. Use MyYes app from Apple App Store (iOS/iPadOS) or Google Play Store (Android) instead.
To check for credit balance via SMS, simply send BAL <Yes number> to 0183301111
To reload using SMS (if you purchased reload codes), simply send REL <Yes number> <reload code> to 0183301111
If you are using Yes on iPhone/iPad, for some reason Speedtest app may detect the provider as Unifi, which is false.
Yes officially supports iPhone with iOS 17.1 onwards, as iOS 17.1 includes Yes’ own carrier bundle beginning with “YES 53.1”. This should make Yes works more realibily with iPhones.
Yes redirects packets going through port 53 to their own DNS server which effectively means Yes blocked custom DNS by IP address (e.g. 8.8.8.8). This can be bypassed by using VPN, DNS over TLS or DNS over HTTPS.

Check Yes 4G’s coverage:

Technical details of Yes 4G LTE network

LTE EARFCNs used:

LTE band number	Frequency	EARFCN(s)
20	800MHz	DL: 6245 UL: 24245
38	2600MHz	38100
40	2300MHz	– 20MHz: 38750/38950/39150 (All of WM, parts of EM) – 10MHz: 39000/39100/39200 (parts of EM)
41	2500MHz	40740

Band 38 & 41 is MFBI of YTL’s 2600MHz spectrum.

Known LTE carrier aggeration (4G+/LTE+/LTE-A) bands:

Band 20 + Band 38 (CA_20A-38A)
Band 38 + Band 40 (CA_38A-40A)
Band 20 + Band 40 (CA_20A-40A)
Band 40 + Band 41 (CA_40A-41A)
Band 20 + Band 38 + Band 40 (CA_20A-38A-40A)

Source

LTE eNB pattern:

Yes uses 6-digit eNB number for their cell towers.
They usually uses x0xxxx and x7xxxx for eNB numbering.
x7xxxx is commonly used for towers inside/near schools & vocational colleges.
First digit indicates region the tower are in.

First digit	State/federal territory
1	Kuala Lumpur/Negeri Sembilan/Putrajaya/Selangor
2	Kedah/Penang/Perak/Perlis
3	Johor/Malacca
4	Kelantan/Pahang/Terengganu
5	Labuan/Sabah
6	Sarawak

Towers:

YTL installs their RANs (antennas) inside most (not all) TM Exchanges throughout Malaysia.
It seems like that Yes’ indoor coverage (like shopping malls, underground stations, etc.) is mostly only available in YTL-owned buildings (with some exceptions like Lowyat Plaza, The Curve) & MRT underground line (SBK/Putrajaya line). You might want to use another telco if you frequent indoors.
Most (if not all) YTL towers inside schools nationwide doesn’t have (or brief) backup power in case of blackouts.

SIM Card:

Yes SIM cards has two IMSIs, one (Yes’ own) for use inside Malaysia and one (StarHub Singapore) for roaming use outside Malaysia.

Two IMSIs above may cause some issues:

Some SIMs may switch to StarHub’s IMSI when there is attach reject and tries to reattach with StarHub’s IMSI.
If the phone does connect to Yes network with StarHub’s IMSI, mobile data service may not work and your device shows roaming icon on status bar/notification.
Restarting the phone should fix this problem. You might want to give it few minutes for it to do so. You also can try swap the SIM to another phone and back to fix the issue.

Receiving/making calls while connected to 5G:

When you make/receive a call to someone, the phone will stay on LTE B28 until someone on the other end answers the call @ you answered the call. As soon as the call is answered by either way, Yes will handover the phone off LTE B28 to their own B20/B38/B40/B41 for the call to continue.

The call would fail instantly after you @ someone on the other end answers the call if:

Your place has LTE B28 signal but no signal from Yes’ own B20/B38/B40/B41
You manually disabled LTE B20/B38/B40/B41 on your phone with something like Network Signal Guru app or MediaTek EngineerMode hidden menu.

I’m unsure if this behaviour is the same on other telcos that uses DNB infra.