diff --git a/phosphor-power-sequencer/src/meson.build b/phosphor-power-sequencer/src/meson.build
index db3ac4a..c1fa67c 100644
--- a/phosphor-power-sequencer/src/meson.build
+++ b/phosphor-power-sequencer/src/meson.build
@@ -6,6 +6,7 @@
 phosphor_power_sequencer_library = static_library(
     'phosphor-power-sequencer',
     'config_file_parser.cpp',
+    'services.cpp',
     implicit_include_directories: false,
     dependencies: [
         nlohmann_json_dep
@@ -21,7 +22,6 @@
     'power_control.cpp',
     'power_interface.cpp',
     'power_sequencer_monitor.cpp',
-    'services.cpp',
     'ucd90x_monitor.cpp',
     'ucd90160_monitor.cpp',
     'ucd90320_monitor.cpp',
diff --git a/phosphor-power-sequencer/src/services.cpp b/phosphor-power-sequencer/src/services.cpp
index 80ad464..9c9ace7 100644
--- a/phosphor-power-sequencer/src/services.cpp
+++ b/phosphor-power-sequencer/src/services.cpp
@@ -61,24 +61,36 @@
     // Initially assume hardware is not present
     bool present{false};
 
-    // Get presence from D-Bus interface/property
-    try
+    // Try to find cached presence value
+    auto it = presenceCache.find(inventoryPath);
+    if (it != presenceCache.end())
     {
-        util::getProperty(INVENTORY_IFACE, PRESENT_PROP, inventoryPath,
-                          INVENTORY_MGR_IFACE, bus, present);
+        present = it->second;
     }
-    catch (const sdbusplus::exception_t& e)
+    else
     {
-        // If exception type is expected and indicates hardware not present
-        if (isExpectedException(e))
+        // Get presence from D-Bus interface/property
+        try
         {
-            present = false;
+            util::getProperty(INVENTORY_IFACE, PRESENT_PROP, inventoryPath,
+                              INVENTORY_MGR_IFACE, bus, present);
         }
-        else
+        catch (const sdbusplus::exception_t& e)
         {
-            // Re-throw unexpected exception
-            throw;
+            // If exception type is expected and indicates hardware not present
+            if (isExpectedException(e))
+            {
+                present = false;
+            }
+            else
+            {
+                // Re-throw unexpected exception
+                throw;
+            }
         }
+
+        // Cache presence value
+        presenceCache[inventoryPath] = present;
     }
 
     return present;
diff --git a/phosphor-power-sequencer/src/services.hpp b/phosphor-power-sequencer/src/services.hpp
index 743c034..255e2c5 100644
--- a/phosphor-power-sequencer/src/services.hpp
+++ b/phosphor-power-sequencer/src/services.hpp
@@ -18,13 +18,12 @@
 #include "pmbus.hpp"
 #include "xyz/openbmc_project/Logging/Entry/server.hpp"
 
-#include <fmt/format.h>
-
 #include <phosphor-logging/lg2.hpp>
 #include <sdbusplus/bus.hpp>
 #include <sdbusplus/exception.hpp>
 
 #include <cstdint>
+#include <format>
 #include <map>
 #include <memory>
 #include <string>
@@ -127,6 +126,15 @@
         createPMBus(uint8_t bus, uint16_t address,
                     const std::string& driverName = "",
                     size_t instance = 0) = 0;
+
+    /**
+     * Clear any cached data.
+     *
+     * Some data may be cached for performance reasons, such as hardware
+     * presence.  Clearing the cache results in the latest data being obtained
+     * by a subsequent method calls.
+     */
+    virtual void clearCache() = 0;
 };
 
 /**
@@ -188,11 +196,17 @@
                     const std::string& driverName = "",
                     size_t instance = 0) override
     {
-        std::string path = fmt::format("/sys/bus/i2c/devices/{}-{:04x}", bus,
+        std::string path = std::format("/sys/bus/i2c/devices/{}-{:04x}", bus,
                                        address);
         return std::make_unique<PMBus>(path, driverName, instance);
     }
 
+    /** @copydoc Services::clearCache() */
+    virtual void clearCache() override
+    {
+        presenceCache.clear();
+    }
+
   private:
     /**
      * Returns whether the specified D-Bus exception is one of the expected
@@ -206,6 +220,13 @@
      * D-Bus bus object.
      */
     sdbusplus::bus_t& bus;
+
+    /**
+     * Cached presence data.
+     *
+     * Map from inventory paths to presence values.
+     */
+    std::map<std::string, bool> presenceCache{};
 };
 
 } // namespace phosphor::power::sequencer
diff --git a/phosphor-power-sequencer/test/meson.build b/phosphor-power-sequencer/test/meson.build
index 4f6b167..6bce451 100644
--- a/phosphor-power-sequencer/test/meson.build
+++ b/phosphor-power-sequencer/test/meson.build
@@ -4,6 +4,7 @@
                 'config_file_parser_tests.cpp',
                 'rail_tests.cpp',
                 dependencies: [
+                    gmock,
                     gtest,
                     nlohmann_json_dep
                 ],
diff --git a/phosphor-power-sequencer/test/mock_services.hpp b/phosphor-power-sequencer/test/mock_services.hpp
index 78ccbc2..c0544f0 100644
--- a/phosphor-power-sequencer/test/mock_services.hpp
+++ b/phosphor-power-sequencer/test/mock_services.hpp
@@ -44,7 +44,7 @@
     MOCK_METHOD(void, logInfoMsg, (const std::string& message), (override));
     MOCK_METHOD(void, logError,
                 (const std::string& message, Entry::Level severity,
-                 std::map<std::string, std::string>& additionalData),
+                 (std::map<std::string, std::string> & additionalData)),
                 (override));
     MOCK_METHOD(bool, isPresent, (const std::string& inventoryPath),
                 (override));
@@ -52,12 +52,12 @@
                 (override));
 
     virtual std::unique_ptr<PMBusBase>
-        createPMBus(uint8_t bus, uint16_t address,
-                    const std::string& driverName = "",
-                    size_t instance = 0) override
+        createPMBus(uint8_t, uint16_t, const std::string&, size_t) override
     {
         return std::make_unique<MockPMBus>();
     }
+
+    MOCK_METHOD(void, clearCache, (), (override));
 };
 
 } // namespace phosphor::power::sequencer