diff --git a/src/devices/machine/m3002.cpp b/src/devices/machine/m3002.cpp
index 1e021571896..12c730c1db7 100644
--- a/src/devices/machine/m3002.cpp
+++ b/src/devices/machine/m3002.cpp
@@ -222,7 +222,7 @@ void m3002_device::bcd_increment(u8 location)
 u8 m3002_device::max_date() const
 {
 	if (m_ram[4] == 0x02)
-		return (m_ram[5] & 0x03) == 0x00 ? 0x29 : 0x28;
+		return (m_ram[5] & 0x03) == ((m_ram[5] & 0x10) >> 3) ? 0x29 : 0x28;
 	else
 		return BIT(0x20250, m_ram[4]) ? 0x30 : 0x31;
 }